Signal processing device, signal processing method, camera system, video system, and server

ABSTRACT

To enable HDR video signals of a plurality of signal interfaces to be satisfactorily handled. 
     [Solution] A processing unit processes a linear high dynamic range video signal and obtains a high dynamic range video signal that has undergone a grayscale compression process. The processing unit is able to perform grayscale compression processes of a plurality of signal interfaces. For example, when a grayscale compression process of another signal interface other than a reference signal interface is performed, the processing unit further performs a process of adding characteristics of system gamma of the reference signal interface and a process of cancelling out characteristics of system gamma of the other signal interface.

RELATED APPLICATIONS

This application is a continuation U.S. application Ser. No. 16/099,803,filed on Nov. 8, 2018, which is a '371 National Phase of InternationalApplication No. PCT/JP2017/023452, filed on Jun. 26, 2017, which claimspriority to Japanese Patent Applications No. 2016-126933, filed on Jun.27, 2016 and No. 2017-123489, filed on Jun. 23, 2017. The entiredisclosures of the prior applications are hereby incorporated byreference in their entirety.

TECHNICAL FIELD

The present technology relates to a signal processing device, a signalprocessing method, a camera system, a video system, and a server, andparticularly relates to a signal processing device that handles highdynamic range video signals, and the like.

BACKGROUND ART

Cameras that output high dynamic range (HDR) video signals are known inthe related art (e.g., refer to Patent Literature 1). Various signalinterfaces have been suggested as signal interfaces for HDR videosignals. As a signal interface, for example, Hybrid Log-Gamma (HLG),Perceptual Quantizer (PQ), S-Log 3, and the like are known.

When signal interfaces vary, an opto-electrical transfer function (OETF)for performing a grayscale compression process and an electro-opticaltransfer function (EOTF) for performing a grayscale decompressionprocess differ, and an opto-optical transfer function that is a videocorrection characteristic during display of a monitor also differs.

With regard to an OETF and an EOTF, basically an OETF of an output sideand an EOTF of a reception side cancel out each other. Thus, even if HDRvideo signal interfaces vary and thus an OETF and an EOTF vary, anactual impact on a video displayed on a monitor is small. However, sincean OOTF is a video correction characteristic during display of amonitor, if signal interfaces vary and thus the OOTF varies, a videodisplayed on the monitor may look different even with the same videosignal (camera video).

CITATION LIST Patent Literature

Patent Literature 1: JP 2015-115789A

DISCLOSURE OF INVENTION Technical Problem

An objective of the present technology is to enable HDR video signals ofa plurality of signal interfaces to be satisfactorily handled.

Solution to Problem

A concept of the present technology is a signal processing deviceincluding: a processing unit configured to process a linear high dynamicrange video signal and obtain a high dynamic range video signal that hasundergone a grayscale compression process. The processing unit is ableto perform grayscale compression processes of a plurality of signalinterfaces.

In the present technology, the processing unit processes a linear highdynamic range (HDR) video signal and obtains a high dynamic range videosignal that has undergone a grayscale compression process. For example,an imaging unit obtains a linear HDR video signal. The processing unitis able to perform the grayscale compression processes of a plurality ofsignal interfaces.

In the present technology described above, the processing unit is ableto perform the grayscale compression processes of the plurality ofsignal interfaces. Thus, HDR video signals that have undergone thegrayscale conversion processes of the plurality of signal interfaces canbe obtained, and thereby usability can be improved.

Note that in the present technology, for example, the processing unitmay further perform at least a process of adding characteristics ofsystem gamma of a reference signal interface when a grayscalecompression process of another signal interface other than the referencesignal interface is performed.

In this case, in a case in which an HDR video signal that has undergonea grayscale compression process of another signal interface is monitoredon a monitor compatible with the interface, the video has undergonesignal processing that makes it identical to a video appearing in a casein which an HDR video signal that has undergone the grayscalecompression process of the reference signal interface is monitored on amonitor compatible with the interface (reference monitor). Thus, even ina case in which an HDR video signal that has undergone a grayscalecompression process of another signal interface other than the referencesignal interface is to be output, camera adjustment (video adjustment)can be performed on the basis of a video on the reference monitor.

In addition, another concept of the present technology is a signalprocessing device including: a processing unit configured to process thelinear high dynamic range video signal and thereby obtain a high dynamicrange video signal that has undergone a grayscale compression process ofa reference signal interface; and a signal conversion unit configured toconvert the high dynamic range video signal that has undergone thegrayscale compression process of the reference signal interface into ahigh dynamic range video signal that has undergone a grayscalecompression process of another signal interface other than the referencesignal interface. The signal conversion unit performs at least eachprocess of a grayscale decompression process corresponding to thegrayscale compression process of the reference signal interface, aprocess of adding characteristics of system gamma of the referencesignal interface, and a grayscale compression process of the othersignal interface on the high dynamic range video signal that hasundergone the grayscale compression process of the reference signalinterface.

In the present technology, the processing unit processes a linear highdynamic range (HDR) videos signal and obtains an HDR video signal thathas undergone the grayscale compression process of the reference signalinterface. For example, an imaging unit obtains a linear HDR videosignal. The signal conversion unit converts the HDR video signal thathas undergone the grayscale compression process of the reference signalinterface into a high dynamic range video signal that has undergone agrayscale compression process of another signal interface other than thereference signal interface.

The signal conversion unit performs a process of converting the highdynamic range video signal that has undergone the grayscale compressionprocess of the reference signal interface into a state in which agrayscale compression process of another signal interface has beenperformed. That is, the signal conversion unit performs the grayscaledecompression process corresponding to the grayscale compression processof the reference signal interface and the grayscale compression processof the other signal interface on the HDR video signal that has undergonethe grayscale compression process of the reference signal interface.Furthermore, the signal conversion unit performs at least the process ofadding the characteristics of system gamma of the reference signalinterface to the HDR video signal that has undergone the grayscalecompression process of the reference signal interface.

In the present technology described above, the signal conversion unitperforms at least the process of adding the characteristics of thesystem gamma of the reference signal interface to the HDR video signalthat has undergone the grayscale compression process of the referencesignal interface.

In this case, in a case in which an HDR video signal that has undergonea grayscale compression process of another signal interface obtained bythe signal conversion unit is monitored on a monitor compatible with theinterface, the video is identical to a video appearing in a case inwhich an HDR video signal that has undergone the grayscale compressionprocess of the reference signal interface is monitored on a monitorcompatible with the interface (reference monitor). Thus, even in a casein which an HDR video signal that has undergone a grayscale compressionprocess of another signal interface other than the reference signalinterface is obtained and used by the signal conversion unit, cameraadjustment (video adjustment) can be performed on the basis of a videoon the reference monitor.

In addition, another concept of the present technology is a video systemincluding: an input unit including a plurality of input apparatuses thatinput a high dynamic range video signal that has undergone a grayscalecompression process of a reference signal interface; an extraction unitconfigured to selectively extract a predetermined high dynamic rangevideo signal from the plurality of input apparatuses; and an output unitconfigured to output a video signal based on the predetermined highdynamic range video signal. The output unit is able to output at least ahigh dynamic range video signal that has undergone a grayscalecompression process of another high dynamic range video signal interfaceother than the reference high dynamic range interface, in addition tothe high dynamic range video signal that has undergone the grayscalecompression process of the reference high dynamic range interface, andthe output unit obtains the high dynamic range video signal that hasundergone the grayscale compression process of the other signalinterface by performing at least each process of a grayscaledecompression process corresponding to the grayscale compression processof the reference signal interface, a process of adding characteristicsof system gamma of the reference signal interface, and the grayscalecompression process of the other signal interface on the predeterminedhigh dynamic range video signal when the high dynamic range video signalthat has undergone the grayscale compression process of the other signalinterface is to be output.

The video system of the present technology has the input unit, theextraction unit, and the output unit. The input unit has the pluralityof input apparatuses that input a high dynamic range (HDR) video signalthat has undergone the grayscale compression process of the referencesignal interface. The extraction unit selectively extracts apredetermined HDR video signal from the plurality of input apparatuses.

The output unit outputs a video signal on the basis of a predeterminedHDR video signal. The output unit is able to output at least an HDRvideo signal that has undergone a grayscale compression process ofanother signal interface other than the reference signal interface inaddition to the HDR video signal that has undergone the grayscalecompression process of the reference signal interface.

In addition, when an HDR video signal that a undergone the grayscalecompression process of another signal interface is to be output, theoutput unit performs a process of converting a predetermined HDR videosignal (an HDR video signal that has undergone the grayscale compressionprocess of the reference signal interface) into a state in which thegrayscale compression process of the other signal interface has beenperformed. That is, the output unit performs the grayscale decompressionprocess corresponding to the grayscale compression process of thereference signal interface and the grayscale compression process of theother signal interface on the predetermined HDR video signal.Furthermore, the output unit performs at least a process of addingcharacteristics of system gamma of the reference signal interface to thepredetermined HDR video signal.

In the present technology described above, the plurality of inputapparatuses of the input unit input an HDR video signal that hasundergone the grayscale compression process of the reference signalinterface, and a predetermined HDR video signal extracted by theextraction unit turns into an HDR video signal that has undergone thegrayscale compression process of the reference signal interface at alltimes. Thus, video adjustment of the plurality of input apparatuses canbe uniformly performed in monitoring of the monitor compatible with thereference signal interface.

In addition, in the present technology, when an HDR video signal thathas undergone a grayscale compression process of another signalinterface is to be output, the output unit performs at least the processof adding characteristics of system gamma of the reference signalinterface. Thus, in a case in which the HDR video signal that hasundergone the grayscale compression process of the other signalinterface is monitored on a monitor compatible with the interface, thevideo can be made identical to a video (adjusted video) appearing in acase in which the above-described predetermined HDR video signal ismonitored on a monitor compatible with the reference signal interface.

Note that, in the present technology, for example, the input unit mayinclude a camera system, and the camera system may have an imaging unitthat obtains a linear HDR video signal, and a processing unit thatprocesses the linear HDR video signal and obtains an HDR video signalthat has undergone the grayscale compression process of the referencesignal interface.

In addition, in the present technology, for example, the input unit mayinclude a signal conversion unit that converts the HDR video signal thathas undergone the grayscale compression process of the other signalinterface other than the reference signal interface into the HDR videosignal that has undergone the grayscale compression process of thereference signal interface, and the signal conversion unit may performat least each process of the grayscale decompression processcorresponding to the grayscale compression process of the other signalinterface, a process of adding a characteristic that cancels out thecharacteristics of system gamma of the reference signal interface, andthe grayscale compression process of the reference signal interface onthe HDR video signal that has undergone the grayscale compressionprocess of the other signal interface.

In this case, in a case in which the HDR video signal that has undergonethe grayscale compression process of the reference signal interfaceobtained by the signal conversion unit is monitored on a monitorcompatible with the interface, the video can be made identical to avideo appearing in a case in which an HDR video signal that hasundergone a grayscale compression process of another signal interface ismonitored on a monitor compatible with the interface.

In addition, in the present technology, for example, the output unit maybe further able to output a standard dynamic range (SDR) video signal.In this case, for example, information of a predetermined HDR videosignal and information of an SDR video signal produced on the basis ofthe predetermined HDR video signal are added to the predetermined HDRvideo signal, and when the output unit outputs the SDR video signal, thepredetermined HDR video signal may be processed on the basis of theinformation added to the predetermined HDR video signal and thereby theSDR video signal may be obtained.

Advantageous Effects of Invention

According to the present technology, HDR video signals of a plurality ofsignal interfaces can be satisfactorily handled. Note that, effectsdescribed in the present specification are merely illustrative and notlimitative, and additional effects may be exhibited.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram illustrating a configuration example of acamera system as a first embodiment.

FIG. 2 is a diagram illustrating a detailed configuration example of anHDR camera processing unit.

FIG. 3 is a block diagram illustrating a configuration example of acamera system as a second embodiment.

FIG. 4 is a block diagram illustrating a configuration example of acamera system as a third embodiment.

FIG. 5 is a block diagram illustrating a configuration example of avideo system as a fourth embodiment.

FIG. 6 is a block diagram illustrating a configuration example of acamera, a CCU, a control panel, and the like of the video system.

FIG. 7 is a block diagram illustrating a detailed configuration exampleof an HDR camera processing unit and an SDR camera processing unitconstituting a CCU.

FIG. 8 is a block diagram illustrating another configuration example ofa camera, a CCU, a control panel, and the like of the video system.

FIG. 9 is a block diagram illustrating a detailed configuration exampleof an inverse HDR camera processing unit and an SDR camera processingunit constituting the CCU.

FIG. 10 is a block diagram illustrating a detailed configuration exampleof HDR converters of the video system.

FIG. 11 is a block diagram illustrating another detailed configurationexample of HDR converters of the video system.

FIG. 12 is a block diagram illustrating a configuration example of anSDR converter of the video system.

FIG. 13 is a block diagram illustrating a detailed configuration exampleof an inverse HDR camera processing unit and an SDR camera processingunit constituting the SDR converter.

FIG. 14 is a block diagram illustrating configuration examples of HDRconverters.

FIG. 15 is a diagram for describing that a video signal produced in asituation in which a monitor side does not have an OOTF function as anHDR-B video signal or an HDR-C video signal input to the HDR convertercan be taken into account.

FIG. 16 is a diagram for describing a case in which a process of addinga system gamma (OOTF) is not performed in signal processing of an HDR-Cvideo signal on an output side.

FIG. 17 is a block diagram illustrating a configuration example of anHDR converter.

FIG. 18 is a block diagram illustrating a configuration example of anHDR converter.

FIG. 19 is a block diagram illustrating a configuration example of anHDR production live system as a fifth embodiment.

FIG. 20 is a block diagram illustrating a configuration example of aserver.

FIG. 21 is a block diagram illustrating a configuration example of anOETF conversion unit.

FIG. 22 is a diagram illustrating representative examples of actual setvalues of the OETF conversion unit.

FIG. 23 is a flowchart showing an example of a control process of theOETF conversion unit of a CPU in a case in which files having differenttypes of material information (signal interface information) from astorage are continuously reproduced.

MODE(S) FOR CARRYING OUT THE INVENTION

Embodiments for implementing the invention (which will also be referredto as embodiments) will be described below. Note that description willbe provided in the following order.

1. First Embodiment 2. Second Embodiment 3. Third Embodiment 4. FourthEmbodiment 5. Fifth Embodiment

6. Modified examples

1. FIRST EMBODIMENT [Configuration Example of Camera System]

FIG. 1 illustrates a configuration example of a camera system 10A as afirst embodiment. The camera system 10A is configured such that a linearhigh dynamic range (HDR) video signal obtained by a camera 11 istransmitted to a Camera Control Unit (CCU) 12 serving as a signalprocessing unit. Here, being linear means that a grayscale compressionprocessing is not performed. The camera 11 and the CCU 12 are connectedthrough a camera cable 13 including optical fibers and the like.

The camera 11 has a CPU 111, an imaging unit 112, a pre-processing unit113, and a transmission unit 114. The CPU 111 controls operations ofeach of the units of the camera 11 and further communicates with a CPU121 of the CCU 12 through the camera cable 13. The imaging unit 112 hasan image sensor with, for example, a UHD (8K, 4K, etc.) or HDresolution, and outputs an HDR video signal as a captured video signal.

Here, 4K resolution is a resolution with about 4000 pixels horizontallyabout 2000 pixels vertically, for example, 4096×2160 or 3840×2160, and8K resolution is a resolution in which there are twice as many pixelsboth vertically and horizontally as in 4K resolution. In addition, an HDresolution is, for example, a resolution in which there half as manypixels vertically and horizontally as in 4K resolution.

The pre-processing unit 113 is a processor including a circuit, forexample, a field-programmable gate array (an FPGA), an applicationspecific integrated circuit (an ASIC), or the like, and performs acorrection process of an optical system such as lenses, a correctionprocess caused by a variation of image sensors, or the like with respectto HDR video signals output from the imaging unit 112. The transmissionunit 114 is a circuit having a communication interface and transmits HDRvideo signals processed by the pre-processing unit 113 to the CCU 12.

The CCU 12 has the CPU 121, a transmission unit 122, an HDR cameraprocessing (HDR-CAM processing) unit 123, an OETF-A⋅formatter unit 124,an OETF-B⋅formatter unit 125, an OOTF-C unit 126, and an inverseEOTF-C-formatter unit 127. The CPU 121 controls operations of each ofthe units of the CCU 12, further communicates with the CPU 111 of thecamera 11 through the camera cable 13, and communicates with a CPU 151of a control panel 15 connected thereto via a communication path 14 of alocal area network (LAN) or the like.

The control panel 15 has an operation input unit 152 in addition to theCPU 151. The CPU 151 receives various control commands and settinginformation input by a producer such as a video engineer (VE) using theoperation input unit 152 and transmits the commands and information tothe CPU 121 of the CCU 12 via the communication path 14.

The transmission unit 122 is a circuit having a communication interface,and receives a linear HDR video signal transmitted from the camera 11.The HDR camera processing unit 123 is a processor including a circuit,for example, an FPGA, an ASIC, or the like, and performs a process suchas color gamut conversion or detail (contour) correction on the linearHDR video signal received by the transmission unit 122.

FIG. 2 illustrates a detailed configuration example of the HDR cameraprocessing unit 123. The HDR camera processing unit 123 has an HDR gainadjustment unit 131, a linear-matrix unit 132, a black-level unit 133,and a detail unit 134.

The HDR gain adjustment unit 131 controls a master gain with respect tothe linear HDR video signal received by the transmission unit 122 (seeFIG. 1) and a gain of signals of each of the primary colors R, G, and Bfor white balance adjustment. The linear-matrix unit 132 performs aprocess of color gamut conversion on the HDR video signal output fromthe HDR gain adjustment unit 131.

The black-level unit 133 adjusts a black level of the HDR video signaloutput from the linear-matrix unit 132. The detail unit 134 performs aprocess of detail (contour) correction on the HDR video signal outputfrom the black-level unit 133. The HDR video signal output from thedetail unit 134 is an output of the HDR camera processing unit 123.

Returning to FIG. 1, the OETF-A⋅formatter unit 124 is a processorincluding a circuit, for example, an FPGA, an ASIC, or the like, andperforms a grayscale compression process of a signal interface A on thelinear HDR video signal output from the HDR camera processing unit 123.The grayscale compression process refers to a process of compressing abit length from a linear area using an opto-electrical transfer function(OETF) for the signal interface A. The signal interface A is, forexample, “S-Log 3.” In addition, the OETF-A⋅formatter unit 124 convertsthe grayscale-compressed HDR video signal from the RGB domain into the Ycolor difference domain, and obtains an HDR video signal “HDR OETF-A”that has undergone the grayscale compression process of the signalinterface A.

The HDR video signal “HDR OETF-A” obtained by the OETF-A⋅formatter unit124 of the CCU 12 as described above can be monitored on a monitor 16corresponding to the signal interface A. The monitor 16 has an inverseOETF-A unit and an OOTF-A unit. The inverse OETF-A unit performs agrayscale decompression process corresponding to the grayscalecompression process of the signal interface A on the HDR video signal“HDR OETF-A.” The grayscale decompression process mentioned here isperformed using inverse characteristics of the opto-electrical transferfunction (OETF) for the signal interface A. In addition, the OOTF-A unitadds characteristics of system gamma of the signal interface A to theHDR video signal “HDR OETF-A.” Accordingly, a video displayed on themonitor 16 is corrected using the characteristics of the system gamma ofthe signal interface A.

the OETF-B⋅formatter unit 125 is a processor including a circuit, forexample, an FPGA, an ASIC, or the like, and performs a grayscalecompression process of a signal interface B on the linear HDR videosignal output from the HDR camera processing unit 123. The grayscalecompression process refers to a process of compressing a bit length froma linear area using an opto-electrical transfer function (OETF) for thesignal interface B. The signal interface B is, for example, “HybridLog-Gamma (HLG).” In addition, the OETF-B⋅formatter unit 125 convertsthe grayscale-compressed HDR video signal from the RGB domain into the Ycolor difference domain, and obtains an HDR video signal “HDR OETF-B”that has undergone the grayscale compression process of the signalinterface B.

The HDR video signal “HDR OETF-B” obtained by the OETF-B⋅formatter unit125 of the CCU 12 as described above can be monitored on a monitor 17corresponding to the signal interface B. The monitor 17 has an inverseOETF-B unit and an OOTF-B unit. The inverse OETF-B unit performs agrayscale decompression process corresponding to the grayscalecompression process of the signal interface B on the HDR video signal“HDR OETF-B.” The grayscale decompression process mentioned here isperformed using inverse characteristics of the opto-electrical transferfunction (OETF) for the signal interface B. In addition, the OOTF-B unitadds characteristics of system gamma of the signal interface B to theHDR video signal “HDR OETF-B.” Accordingly, a video displayed on themonitor 17 is corrected using the characteristics of the system gamma ofthe signal interface B.

The OOTF-C unit 126 is a processor including a circuit, for example, anFPGA, an ASIC, or the like, and adds characteristics of system gamma(opto-optical transfer function or OOTF) of a signal interface C to thelinear HDR video signal output from HDR camera processing unit 123.

The inverse EOTF-C-formatter unit 127 is a processor including acircuit, for example, an FPGA, an ASIC, or the like, and performs thegrayscale compression process of the signal interface C on the HDR videosignal output from the OOTF-C unit 126. The grayscale compressionprocess mentioned here refers to a process of compressing a bit lengthfrom a linear area using inverse characteristics of an electro-opticaltransfer function (EOTF) for the signal interface C. The signalinterface C is, for example, a “Perceptual Quantizer (PQ).” In addition,the inverse EOTF-C-formatter unit 127 converts the grayscale-compressedHDR video signal from the RGB domain into the Y color difference domainand obtains an HDR video signal “HDR EOTF-C” that has undergone thegrayscale compression process of the signal interface C.

The HDR video signal “HDR EOTF-C” obtained by the OETF-C-formatter unit127 of the CCU 12 as described above can be monitored by a monitor 18corresponding to the signal interface C. The monitor 18 has an EOTF-Cunit. The EOTF-C unit performs the grayscale decompression processcorresponding to the grayscale compression process of the signalinterface C on the HDR video signal “HDR EOTF-C.” The grayscaledecompression process mentioned here is performed using anelectro-optical transfer function (EOTF) for the signal interface C.Accordingly, a video displayed on the monitor 18 is corrected usingcharacteristics of system gamma of the signal interface C.

As described above, the CCU 12 of the camera system 10A illustrated inFIG. 1 obtains the HDR video signals that have undergone the grayscalecompression processes of the signal interfaces A, B, and C. Thus, acamera system with improved usability can be provided.

Note that, although the HDR video signals that have undergone thegrayscale compression processes of the signal interfaces A, B, and C aresimultaneously output from the CCU 12 in the camera system 10Aillustrated in FIG. 1, a configuration in which one of the HDR videosignals is selectively output can also be adopted. In this case, forexample, a processor (a processing unit) can be disposed subsequent tothe HDR camera processing unit 123 and selectively switch between “theOETF-A⋅formatter unit 124,” “the OETF-B⋅formatter unit 125,” or the “theOOTF-C unit 126 and the inverse EOTF-C-formatter unit 127” to give theoutput function and thereby a decrease in a circuit size can also beachieved.

2. SECOND EMBODIMENT [Configuration Example of Camera System]

FIG. 3 illustrates a configuration example of a camera system 10B as asecond embodiment. In FIG. 3, the same reference numerals are given toparts corresponding to those of FIG. 1, and detailed description thereofwill be appropriately omitted. The camera system 10B has a configurationin which a linear HDR video signal obtained by a camera 11 istransmitted to a camera control unit (CCU) 12B serving as a signalprocessing unit.

The CCU 12B has the CPU 121, a transmission unit 122, an HDR cameraprocessing unit 123, an OETF-A⋅formatter unit 124, an OETF-B⋅formatterunit 125, an inverse EOTF-C-formatter unit 127, OOTF-A units 141 and143, and an inverse OOTF-B unit 142. The CPU 121 controls operations ofeach of the units of the CCU 12B, further communicates with the CPU 111of the camera 11 through the camera cable 13, and communicates with aCPU 151 of a control panel 15 connected thereto via a communication path14 of a LAN or the like.

The transmission unit 122 is a circuit having a communication interface,and receives a linear HDR video signal transmitted from the camera 11.The HDR camera processing unit 123 performs a process such as colorgamut conversion or detail (contour) correction on the linear HDR videosignal received by the transmission unit 122.

The OETF-A⋅formatter unit 124 performs a grayscale compression processof the signal interface A on the linear HDR video signal output from theHDR camera processing unit 123. The grayscale compression processmentioned here refers to a process of compressing a bit length from alinear area using the opto-electrical transfer function (OETF) for thesignal interface A. In addition, the OETF-A⋅formatter unit 124 convertsthe grayscale-compressed HDR video signal from the RGB domain to the Ycolor difference domain and obtains an HDR video signal “HDR OETF-A”that has undergone the grayscale compression process of the signalinterface A.

The HDR video signal “HDR OETF-A” obtained by the OETF-A⋅formatter unit124 of the CCU 12B as described above can be monitored by a monitor 16corresponding to the signal interface A. The monitor 16 has an inverseOETF-A unit and an OOTF-A unit. Accordingly, a video displayed on themonitor 16 is corrected with characteristics of system gamma of thesignal interface A.

The OOTF-A unit 141 is a processor including a circuit, for example, anFPGA, an ASIC, or the like, and adds characteristics of the system gamma(OOTF) of the signal interface A to the linear HDR video signal outputfrom the HDR camera processing unit 123. The inverse OOTF-B unit 142 isa processor including a circuit, for example, an FPGA, an ASIC, or thelike, and adds characteristics that cancel out the characteristics ofsystem gamma (OOTF) of the signal interface B on the HDR video signaloutput from the OOTF-A unit 141.

The OETF-B⋅formatter unit 125 performs the grayscale compression processof the signal interface B on the HDR video signal output from theinverse OOTF-B unit 142. The grayscale compression process mentionedhere refers to a process of compressing a bit length from a linear areausing the opto-electrical transfer function (EOTF) for the signalinterface B. In addition, the OETF-B⋅formatter unit 125 converts thegrayscale-compressed HDR video signal from the RGB domain to the Y colordifference domain and thereby obtains an HDR video signal “HDR OETF-B”that has undergone the grayscale compression process of the signalinterface B.

The HDR video signal “HDR OETF-B” obtained by the OETF-B⋅formatter unit125 of the CCU 12B as described above can be monitored by the monitor 17corresponding to the signal interface B. The monitor 17 has an inverseOETF-B unit and an OOTF-B unit. Since the OOTF-A unit 141 and theinverse OOTF-B unit 142 are present in the system of the HDR videosignal “HDR OETF-B” of the CCU 12B as described above, a video displayedon the monitor 17 is corrected using the characteristics of the systemgamma of the signal interface A, like the video displayed on theabove-described monitor 16.

The OOTF-A unit 143 is a processor including a circuit, for example, anFPGA, an ASIC, or the like, and adds characteristics of the system gamma(OOTF) of the signal interface A to the linear HDR video signal outputfrom the HDR camera processing unit 123.

The inverse EOTF-C-formatter unit 127 performs a grayscale compressionprocess of the signal interface C on the HDR video signal output fromthe OOTF-A unit 143. The grayscale compression process mentioned hererefers to a process of compressing a bit length from a linear area usinginverse characteristics of the electro-optical transfer function (EOTF)of the signal interface C. In addition, the inverse EOTF-C-formatterunit 127 converts the grayscale-compressed HDR video signal from the RGBdomain to the Y color difference domain and then obtains an HDR videosignal “HDR EOTF-C” that has undergone the grayscale compression processof the signal interface C. In terms of signal interface, OOTF-C shouldbe added, however, OOTF-A includes OOTF-C, and it can be regarded thatsignal processing with [OOTF-A-OOTF-C] has been performed as videocorrection, and thereby, it can be said that the signal interface ofEOTF-C is complied.

The HDR video signal “HDR EOTF-C” obtained by the inverseOETF-C-formatter unit 127 of the CCU 12B can be monitored on a monitor18 corresponding to the signal interface C. The monitor 18 has an EOTF-Cunit. Since the above-described OOTF-A unit 141 is present and theOOTF-C unit 126 (see FIG. 1) is not present in the system of the HDRvideo signal “HDR OETF-C” of the CCU 12B, a video displayed on themonitor 18 is corrected using the characteristics of the system gamma ofthe signal interface A, like the video displayed on the above-describedmonitor 16.

Having the signal interface A as a reference signal interface in thecamera system 10B illustrated in FIG. 3, when the grayscale compressionprocess of another signal interface other than the reference signalinterface is performed in the CCU 12B as described above, the process ofadding the characteristics of the system gamma of the reference signalinterface and the process of cancelling out the characteristics ofsystem gamma of the other signal interface are performed.

In this case, in a case in which an HDR video signal that has undergonea grayscale compression process of another signal interface is monitoredon a monitor compatible with the interface, the video is made identicalto a video appearing in a case in which an HDR video signal that hasundergone the grayscale compression process of the reference signalinterface is monitored on a monitor compatible with the interface(reference monitor). Thus, even in a case in which an HDR video signalthat has undergone a grayscale compression process of another signalinterface other than the reference signal interface is to be output,camera adjustment (video adjustment) can be performed on the basis of avideo on the reference monitor.

Note that, although the HDR video signals that have undergone thegrayscale compression processes of the signal interfaces A, B, and C aresimultaneously output from the CCU 12B in the camera system 10Billustrated in FIG. 3, a configuration in which one of the HDR videosignals is selectively output can also be adopted. In this case, forexample, a processor (a processing unit) can be disposed subsequent tothe HDR camera processing unit 123 and selectively switch between “theOETF-A⋅formatter unit 124,” “the OOTF-A unit 141, the inverse OOTF-Bunit 142, and the OETF-B⋅formatter unit 125,” or the “the OOTF-A unit143 and the inverse EOTF-C-formatter unit 127” to give the outputfunction and thereby a decrease in a circuit size can also be achieved.

3. THIRD EMBODIMENT [Configuration Example of Camera System]

FIG. 4 illustrates a configuration example of a camera system 10C as athird embodiment. In FIG. 4, the same reference numerals are given toparts corresponding to those of FIGS. 1 and 3, and detailed descriptionthereof will be appropriately omitted. The camera system 10C has aconfiguration in which a linear HDR video signal obtained by a camera 11is transmitted to a camera control unit (CCU) 12C serving as a signalprocessing unit.

In addition, the camera system 10C performs a signal conversion processon the HDR video signal that has undergone the grayscale compressionprocess of the signal interface A output from the CCU 12C using HDRconverters (HDR-Converter) 19 and 20 and the converters respectivelyobtain HDR video signals that have undergone the grayscale compressionprocess of the signal interfaces B and C.

The CCU 12C has the CPU 121, a transmission unit 122, an HDR cameraprocessing unit 123, and an OETF-A⋅formatter unit 124. The CPU 121controls operations of each of the units of the CCU 12C, furthercommunicates with the CPU 111 of the camera 11 through the camera cable13, and communicates with a CPU 151 of a control panel 15 connectedthereto via a communication path 14 of a LAN or the like.

The transmission unit 122 is a circuit having a communication interface,and receives a linear HDR video signal transmitted from the camera 11.The HDR camera processing unit 123 performs a process such as colorgamut conversion or detail (contour) correction on the linear HDR videosignal received by the transmission unit 122.

The OETF-A⋅formatter unit 124 performs a grayscale compression processof the signal interface A on the linear HDR video signal output from theHDR camera processing unit 123. The grayscale compression processmentioned here refers to a process of compressing a bit length from alinear area using the opto-electrical transfer function (OETF) for thesignal interface A. In addition, the OETF-A⋅formatter unit 124 convertsthe grayscale-compressed HDR video signal from the RGB domain to the Ycolor difference domain and obtains an HDR video signal “HDR OETF-A”that has undergone the grayscale compression process of the signalinterface A.

The HDR video signal “HDR OETF-A” obtained by the OETF-A⋅formatter unit124 of the CCU 12C as described above can be monitored by a monitor 16corresponding to the signal interface A. The monitor 16 has an inverseOETF-A unit and an OOTF-A unit. Accordingly, a video displayed on themonitor 16 is corrected with characteristics of system gamma of thesignal interface A.

The HDR converter 19 is a processor including a circuit, for example, anFPGA, an ASIC, or the like, and has a de-formatter unit 144, an inverseOETF-A unit 145, an OOTF-A unit 141, an inverse OOTF-B unit 142, and anOETF-B⋅formatter unit 125.

The de-formatter unit 144 performs a conversion process on the HDR videosignal “HDR OETF-A” that has undergone the grayscale compression processof the signal interface A output from the CCU 12C from the Y colordifference domain to the RGB domain. The inverse OETF-A unit 145performs a grayscale decompression process corresponding to thegrayscale compression process of the signal interface A on the HDR videosignal output from the de-formatter unit 144. The grayscaledecompression process mentioned here is performed using inversecharacteristics of the opto-electrical transfer function (OETF) for thesignal interface A.

The OOTF-A unit 141 adds characteristics of the system gamma (OOTF) ofthe signal interface A to the linear HDR video signal output from theinverse OETF-A unit 145. The inverse OOTF-B unit 142 addscharacteristics that cancel out characteristics of system gamma (OOTF)of the signal interface B to the HDR video signal output from the OOTF-Aunit 141.

The OETF-B⋅formatter unit 125 performs the grayscale compression processof the signal interface B on the HDR video signal output from theinverse OOTF-B unit 142. The grayscale compression process mentionedhere refers to a process of compressing a bit length from a linear areausing the opto-electrical transfer function (OETF) for the signalinterface B. In addition, the OETF-B⋅formatter unit 125 converts thegrayscale-compressed HDR video signal from the RGB domain to the Y colordifference domain and thereby obtains an HDR video signal “HDR OETF-B”that has undergone the grayscale compression process of the signalinterface B.

The HDR video signal “HDR OETF-B” obtained by the HDR converter 19 asdescribed above can be monitored by the monitor 17 corresponding to thesignal interface B. The monitor 17 has an inverse OETF-B unit and anOOTF-B unit. Since the OOTF-A unit 141 and the inverse OOTF-B unit 142are present in the system of the HDR converter 19 as described above, avideo displayed on the monitor 17 is corrected using the characteristicsof the system gamma of the signal interface A, like the video displayedon the above-described monitor 16.

The HDR converter 20 is a processor including a circuit, for example, anFPGA, an ASIC, or the like, and has a de-formatter unit 146, an inverseOETF-A unit 147, an OOTF-A unit 143, and an inverse EOTF-C-formatterunit 127. The de-formatter unit 146 performs a conversion process on theHDR video signal “HDR OETF-A” that has undergone the grayscalecompression process of the signal interface A output from the CCU 12Cfrom the Y color difference domain to the RGB domain.

The inverse OETF-A unit 147 performs the grayscale decompression processcorresponding to the grayscale compression process of the signalinterface A on the HDR video signal output from the de-formatter unit146. The grayscale decompression process mentioned here is performedusing inverse characteristics of the opto-electrical transfer function(OETF) for the signal interface A. The OOTF-A unit 143 adds thecharacteristics of the system gamma (OOTF) of the signal interface A onthe linear HDR video signal output from the inverse OETF-A unit 147.

The inverse EOTF-C-formatter unit 127 performs the grayscale compressionprocess of the signal interface C on the HDR video signal output fromthe OOTF-A unit 143. The grayscale compression process mentioned hererefers to a process of compressing a bit length from a linear area usinginverse characteristics of the electro-optical transfer function (EOTF)for the signal interface C. In addition, the inverse EOTF-C-formatterunit 127 converts the grayscale-compressed HDR video signal from the RGBdomain to the Y color difference domain, and thereby obtains an HDRvideo signal “HDR EOTF-C” that has undergone the grayscale compressionprocess of the signal interface C.

The HDR-C video signal “HDR EOTF-C” obtained by the HDR converter 20 asdescribed above can be monitored on a monitor 18 corresponding to thesignal interface C. The monitor 18 has an EOTF-C unit. Since the OOTF-Aunit 141 is present and the OOTF-C unit 126 (see FIG. 1) is not presentin the system of the HDR converter 20 as described above, a videodisplayed on the monitor 18 is corrected using the characteristics ofthe system gamma of the signal interface A, like the video displayed onthe above-described monitor 16.

Having the signal interface A as a reference signal interface in thecamera system 10C illustrated in FIG. 4, when the grayscale compressionprocess of another signal interface other than the reference signalinterface is performed in the HDR converters 19 and 20 as describedabove, the process of adding the characteristics of the system gamma ofthe reference signal interface and the process of cancelling out thecharacteristics of system gamma of the other signal interface areperformed.

In this case, in a case in which an HDR video signal that has undergonea grayscale compression process of another signal interface is monitoredon a monitor compatible with the interface, the video is made identicalto a video appearing in a case in which an HDR video signal that hasundergone the grayscale compression process of the reference signalinterface is monitored on a monitor compatible with the interface(reference monitor). Thus, even in a case in which an HDR video signalthat has undergone a grayscale compression process of another signalinterface other than the reference signal interface is to be output,camera adjustment (video adjustment) can be performed on the basis of avideo on the reference monitor.

4. FOURTH EMBODIMENT [Configuration Example of Video System]

FIG. 5 illustrates a configuration example of a video system 30 as afourth embodiment. The video system 30 has a predetermined number ofcamera systems each including a camera 31 and a camera control unit(CCU) 32, of which there are 2 in the illustrated example. The camera 31and the CCU 32 are connected by a camera cable 33.

A control panel 35 is connected to the CCU 32 via a communication path34 of a LAN or the like. A high dynamic range (HDR) video signal (HDR-Avideo signal) that has undergone the grayscale compression process ofthe signal interface A and a standard dynamic range (SDR) video signalare output from the CCU 32. In this embodiment, the signal interface Ais set as a reference signal interface (standard signal interface). Thesignal interface Ais, for example, “S-Log 3.”

In addition, the video system 30 has a predetermined number of HDRconverters (HDR-Converter) 36 that convert an HDR signal that hasundergone the grayscale compression process of a signal interface otherthan the signal interface A into an HDR signal (HDR-A video signal) thathas undergone the grayscale compression process of the signal interfaceA, of which there is one in the illustrated example. The HDR converter36 is a processor including a circuit, for example, an FPGA, an ASIC, orthe like. The HDR converter 36 converts, for example, an HDR videosignal (HDR-B video signal) that has undergone the grayscale compressionprocess of the signal interface B or an HDR video signal (HDR-C videosignal) that has undergone the grayscale compression process of thesignal interface C into an HDR-A video signal. The signal interface Bis, for example, an “HLG (Hybrid Log-Gamma),” and the signal interface Cis “PQ (Perceptual Quantizer).”

In addition, the video system 30 has a server (Server) 37 that canperform recording and reproduction of HDR-A video signals. HDR-A videosignals recorded in the server 37 also include an HDR-A video signaloutput from the CCU 32 and an HDR-A video signal output from the HDRconverter 36. Here, the camera system, the HDR converter 36, the server37, and the like are included in input apparatuses.

In addition, the video system 30 has a switcher (Switcher) 38. The HDR-Avideo signal output from the CCU 32 of the camera system is input to theswitcher 38 via a transmission path 39. Here, the information of theHDR-A video signal and information of an SDR video signal are added tothe HDR-A video signal output from the CCU 32 of the camera system. Notethat the SDR video signal output from the CCU 32 of the camera system issupplied to an SDR monitor 41 via a transmission path 40 to bemonitored.

In addition, the HDR-A video signal output from the HDR converter 36 isinput to the switcher 38 via a transmission path 42. In addition, theHDR-A video signal reproduced from the server 37 is also input to theswitcher 38. Note that an HDR-A signal to be recorded is supplied fromthe switcher 38 to the server 37.

The switcher 38 selectively extracts a predetermined HDR-A video signalfrom the HDR-A video signals input from the plurality of inputapparatuses such as the camera system, the HDR converter 36, the server37, and the like. The predetermined HDR-A video signal extracted by theswitcher 38 is transmitted through a main transmission path 43. Notethat the HDR-A video signal is supplied to a monitor 45 corresponding tothe signal interface A via a transmission path 44 to be monitored.

In addition, the video system 30 has an HDR converter (HDR-Converter) 46that converts the HDR-A video signal transmitted on the maintransmission path 43 into an HDR signal that has undergone the grayscalecompression process of a signal interface other than the signalinterface A. The HDR converter 46 is a processor including a circuit,for example, an FPGA, an ASIC, or the like. The HDR converter 46converts the HDR-A video signal into, for example, an HDR-B video signalor an HDR-C video signal. Note that the HDR video signal obtained by theHDR converter 46 is supplied to a monitor 48 for a corresponding signalinterface via a transmission path 47 to be monitored.

In addition, the video system 30 has an SDR converter (SDR Converter) 49that converts the HDR-A video signal transmitted on the maintransmission path 43 into an SDR video signal. In a case in whichinformation of the HDR-A video signal and information of an SDR videosignal are added to the HDR-A video signal, the SDR converter 49processes the HDR-A video signal on the basis of the information andobtains the SDR video signal.

FIG. 6 illustrates a configuration example of the camera 31, the CCU 32,the control panel 35, and the like. The camera 31 has a CPU 311, animaging unit 312, a pre-processing unit 313, and a transmission unit314. The CPU 311 controls operations of each of the units of the camera31 and further communicates with a CPU 321 of the CCU 32 through thecamera cable 33. The imaging unit 312 has an image sensor with, forexample, a UHD (8K, 4K, etc.) or HD resolution, and outputs an HDR videosignal as a captured video signal.

The pre-processing unit 313 is a processor including a circuit, forexample, a field-programmable gate array (an FPGA), an applicationspecific integrated circuit (an ASIC), or the like, and performs acorrection process of an optical system such as lenses, a flawcorrection process caused by a variation of image sensors, or the likewith respect to HDR video signals output from the imaging unit 312. Thetransmission unit 314 is a circuit having a communication interface andtransmits HDR video signals processed by the pre-processing unit 313 tothe CCU 32.

The CCU 32 has the CPU 321, a transmission unit 322, an HDR cameraprocessing (HDR-CAM Process) unit 323, and an SDR camera processing (SDRCAM Process) unit 324. The CPU 321 controls operations of each of theunits of the CCU 32, communicates with the CPU 311 of the camera 31 viaa camera cable 33, and communicates with a CPU 351 of the control panel(Control Panel) 35 connected via a communication path 34 of a local areanetwork (LAN), or the like.

The control panel 35 has an operation input unit 352 in addition to theCPU 351. The CPU 351 receives various control commands and settinginformation input by a producer such as a video engineer (VE) using theoperation input unit 352 and transmits the commands and information tothe CPU 321 of the CCU 32 via the communication path 34.

The transmission unit 322 is a circuit having a communication interface,and receives a linear HDR video signal transmitted from the camera 31.The HDR camera processing unit 323 is a processor including a circuit,for example, an FPGA, an ASIC, or the like, performs processes of colorgamut conversion, detail (contour) correction, grayscale compression,and the like on the linear HDR video signal received by the transmissionunit 322, then obtains an HDR video signal that has undergone thegrayscale compression process of the signal interface A, that is, anHDR-A video signal “HDR OETF-A”, and then transmits the signal to atransmission path 39. The grayscale compression process mentioned hererefers to a process of compressing a bit length from a linear area usingthe opto-electrical transfer function (OETF) for the signal interface A.

The SDR camera processing unit 324 is a processor including a circuit,for example, an FPGA, an ASIC, or the like, obtains an SDR video signalby performing level (gain) conversion, color gamut conversion, kneecorrection, detail (contour) correction, gamma processing, and the likeon the linear HDR video signal received by the transmission unit 322 andthen transmits the signal to a transmission path 40.

Note that information of the HDR-A video signal “HDR OETF-A” obtained bythe HDR camera processing unit 323 and information of the SDR videosignal obtained by the SDR camera processing unit 324 are added to theHDR-A video signal under control of the CPU 321. Note that, as a methodof adding information, the CPU 321 may perform a process of multiplexinginformation with an HDR video stream, or output the information as ametadata file as associated with an HDR data stream to the transmissionpath 39, separately from an HDR video.

FIG. 7 illustrates a detailed configuration example of the HDR cameraprocessing unit 323 and the SDR camera processing unit 324. Note thatthis example is an example in which an HDR video signal has a UHD (8K,4K, etc.) resolution, and the SDR camera processing unit 324 may includea resolution conversion unit, which may convert the signal into an HDsignal and output.

The HDR camera processing unit 323 has an HDR gain adjustment unit 331,a linear matrix (Linear-Matrix) unit 332, a black level (Black-level)unit 333, a detail (Detail) unit 334, and an OETF-A⋅formatter unit 335.

The HDR gain adjustment unit 331 controls a master gain of the linearHDR video signal (Linear HDR Video) received by the transmission unit322 (see FIG. 6) and controls a gain of signals of each of the primarycolors R, G, and B for adjusting white balance. The linear-matrix unit332 performs a linear matrix process for color gamut conversion on theHDR video signal output from the HDR gain adjustment unit 331, ifnecessary. The processing details serve as HDR adjustment parameters asHDR-Color-Gamut information.

The black-level unit 333 adjusts a black level of the HDR video signaloutput from the linear-matrix unit 222 on the basis of information forblack level correction (HDR-Black) that is part of the HDR adjustmentparameter information. The detail unit 334 performs a process of detail(contour) correction on the HDR video signal output from the black-levelunit 333.

The OETF-A⋅formatter unit 335 performs the grayscale compression processof the signal interface A on the HDR video signal output from the detailunit 334 on the basis of OETF information (OETF) that is part of the HDRadjustment parameter information. The grayscale compression processmentioned here refers to a process of compressing a bit length from alinear area using the opto-electrical transfer function (OETF) for thesignal interface A. In addition, the OETF-A⋅formatter unit 335 convertsthe grayscale-compressed HDR video signal from the RGB domain to the Ycolor difference domain and thereby obtains an output HDR-A video signal“HDR OETF-A.”

The CPU 321 adds, as information of the HDR-A video signal, for example,the HDR adjustment parameter information (“HDR-Color Gamut,”“HDR-Black,” and “OETF”) to the HDR-A video signal “HDR OETF-A” andtransmits the signal.

The SDR camera processing unit 324 has a resolution conversion unit 341,an SDR gain adjustment unit 342, a linear matrix (Linear-Matrix) unit343, a black level (Black-level) unit 344, a knee (Knee)-detail (Detail)unit 345, and a gamma (Gamma)-formatter (Formatter) unit 346.

The resolution conversion unit 341 may convert the resolution of thelinear HDR video signal (Linear HDR Video) received by the transmissionunit 322 (see FIG. 6) from UHD to HD. The SDR gain adjustment unit 342controls a master gain of the linear HDR video signal output from theresolution conversion unit 341 and controls a gain of signals of each ofthe primary colors R, G, and B for adjusting white balance on the basisof relative gain (Relative-Gain) information that is part of parameterinformation regarding levels of the SDR video and the HDR video.

The relative gain is a parameter indicating a ratio between a gain forpixel signals in the HDR process and a gain for pixel signals in the SDRprocess to make a contrast ratio between the HDR video and the SDR videoadjustable. For example, a relative gain defines a setting of a multipleof a dynamic range of the HDR video with respect to a dynamic range ofthe SDR video.

With the relative gain, a ratio of a master gain on the SDR process sideto a master gain on the HDR process side can be set to an arbitraryratio, for example 1, ½, or the like. If a ratio of the master gain onthe SDR process side to the master gain on the HDR process side is set,the dynamic range of the HDR video correlating to the dynamic range ofthe SDR video can be obtained.

More specifically, an upper limit reference of the dynamic range of theSDR video is given with reference white (Diffuse-White) chosen by aproducer. By choosing the reference white (Diffuse-White) of the SDRvideo in the video system 30, a reference of the dynamic range of theHDR video (reference white (Diffuse-White) of the HDR video) is alsodetermined on the basis of the correlation based on the relative gain.

The relative gain should be appropriately selected in accordance with aphotographing environment, for example, daytime, night time, an indoorplace, an outdoor place, inside a studio, in sunny weather, in rainyweather, or the like, and the texture of the video should beappropriately selected according to an intended production purpose. Forthis reason, the relative gain is provided as a variable that can handlevarious photographing environments. As a method for preparing therelative gain, a method of comparing a brightness of the appearance ofthe SDR video and the HDR video simultaneously output from the CCU 32with that of the human eye can be conceived. The SDR video and the HDRvideo are compared each time a value of the relative gain is changed,and a relative gain close to the brightness of the appearance of the SDRvideo and the HDR video may be determined as an optimum relative gainfor the photographing environment.

Note that the relative gain may be information for performing a whitebalance process or a contrast process for the SDR video, and forexample, may be information other than a numerical value of a ratio ofan HDR signal to a gain, such as a value of a gain for raw data that isa sensor output value.

Note that a luminance dynamic range of the HDR video is wider than aluminance dynamic range of the SDR video. As an example, when aluminance dynamic range of the SDR video is set to 0 to 100%, aluminance dynamic range of the HDR video is, for example, 0% to 1,300%or 0% to 10,000%.

The linear-matrix unit 343 performs a linear matrix process for colorgamut conversion on the HDR video signal output from the SDR gainadjustment unit 342 on the basis of color gamut information (SDR-ColorGamut) that is part of SDR adjustment parameter information andinformation regarding colors of the SDR video. The black-level unit 344adjusts a black level of the HDR video signal output from thelinear-matrix unit 343 on the basis of information for black levelcorrection (SDR-Black) that is part of the SDR adjustment parameterinformation. The knee-detail unit 345 performs knee correction on theHDR video signal output from the black-level unit 344 to convert thesignal into an SDR video signal on the basis of information regardingknee correction (KNEE) that is part of the SDR adjustment parameterinformation, and further performs detail (contour) correction on the SDRvideo signal.

The gamma⋅formatter unit 346 performs gamma processing on the linear SDRvideo signal output from the knee-detail unit 345 on the basis of gammacharacteristic information (SDR-Gamma) that is part of the SDRadjustment parameter information. In addition, the gamma⋅formatter unit346 converts the signal-processed SDR video from the RGB domain to the Ycolor difference domain and thereby obtains an output SDR video signal.

The CPU 321 adds, as information of the SDR video signal, for example,SDR adjustment parameter information (“Relative-Gain,” “SDR-ColorGamut,” “SDR-Black,” “KNEE,” and “SDR-Gamma”) to the HDR-A video signal“HDR OETF-A” and transmits the signal.

FIG. 8 illustrates another configuration example of the camera 31, theCCU 32, the control panel 35, and the like. In FIG. 8, the samereference numerals are given to parts corresponding to those of FIG. 6,and detailed description thereof will be appropriately omitted. Thecamera 31 has a CPU 311, an imaging unit 312, a pre-processing unit 313,an HDR camera processing (HDR-CAM Process) unit 315, and a transmissionunit 314.

The HDR camera processing unit 315 is a processor including a circuit,for example, an FPGA, an ASIC, or the like, and performs a process ofcolor gamut conversion, detail (contour) correction, grayscalecompression, and the like on a linear HDR video signal processed by thepre-processing unit 313, and thereby obtains an HDR video signal thathas undergone the grayscale compression process of the signal interfaceA, that is, an HDR-A video signal “HDR OETF-A.” Although detaileddescription will be omitted, the HDR camera processing unit 315 has asimilar configuration to the above-described HDR camera processing unit323 (see FIGS. 6 and 7). The transmission unit 314 is a circuit having acommunication interface, and transmits the HDR-A video signal “HDROETF-A” obtained by the HDR camera processing unit 315 to the CCU 32.

Note that, information of the HDR-A video signal “HDR OETF-A” obtainedby the HDR camera processing unit 315 is added to the HDR-A video signalunder control of the CPU 311. This information is, for example, HDRadjustment parameter information (“HTDR-Color Gamut,” “HDR-Black,” and“OETF”), like the information of the HDR-A video signal added to theHDR-A video signal “HDR OETF-A” obtained by the above-described HDRcamera processing unit 323.

The CCU 32 has a CPU 321, a transmission unit 322, an inverse HDR cameraprocessing (Inverse HDR-CAM Process) unit 325, and an SDR cameraprocessing (SDR CAM Process) unit 324. The CPU 321 controls operationsof each unit of the CCU 32, communicates with the CPU 311 of the camera31 through a camera cable 33, and communicates with a CPU 351 of thecontrol panel 35 connected via a communication path 34 of a LAN, or thelike.

The transmission unit 322 is a circuit having a communication interface,and receives the HDR-A video signal “HDR OETF-A” transmitted from thecamera 31 and outputs the signal to a transmission path 39. The HDR-Avideo signal “HDR OETF-A” includes the HDR adjustment parameterinformation (“HDR-Color Gamut,” “HDR-Black,” and “OETF”), for example,added thereto as information of the HDR-A video signal as describedabove.

The inverse HDR camera processing unit 325 is a processor including acircuit, for example, an FPGA, an ASIC, or the like, performs processessuch as conversion from the Y color difference domain into the RGBdomain and inverse conversion of grayscale compression on the HDR-Avideo signal “HDR OETF-A” received by the transmission unit 322, andthen obtains a linear HDR video signal. The operation of the inverse HDRcamera processing unit 302 is performed under control of the CPU 321 onthe basis of the information of the HDR-A video signal added to theHDR-A video signal “HDR OETF-A.”

Note that, although the example in which the information of the HDR-Avideo signal is added to the HDR-A video signal “HDR OETF-A” transmittedfrom the camera 31 has been described above, the information of theHDR-A video signal may be transmitted in communication from the CPU 311of the camera 31 to the CPU 321 of the CCU 32.

The SDR camera processing unit 324 obtains an SDR video signal byperforming level (gain) conversion, color gamut conversion, kneecorrection, detail (contour) correction, gamma processing, and the likeon the linear HDR video signal obtained by the inverse HDR cameraprocessing unit 325, and then transmits the signal to a transmissionpath 40.

Note that, although the information of the HDR-A video signal “HDROETF-A” is added to the HDR-A video signal “HDR OETF-A” received by thetransmission unit 322, when the HDR-A video signal “HDR OETF-A” istransmitted to the transmission path 39, information of the SDR videosignal obtained by the SDR camera processing unit 324, for example, SDRadjustment parameter information (“Relative-Gain,” “SDR-Color Gamut,”“SDR-Black,” “KNEE,” and “SDR-Gamma”) is further added thereto undercontrol of the CPU 321.

FIG. 9 illustrates a detailed configuration example of the inverse HDRcamera processing unit 325 and the SDR camera processing unit 324. Notethat, this is an example in which the HDR video signal has a UHD (8K,4K, etc.) resolution, and the SDR camera processing unit 324 has aresolution conversion unit.

The inverse HDR camera processing unit 325 has a de-formatter(De-Formatter) unit 361, an inverse OETF (Inverse-OETF) unit 362, aremove black-level (Remove-Black-level) unit 363.

The de-formatter 361 performs a process of converting the HDR-A videosignal “HDR OETF-A” received by the transmission unit 322 (see FIG. 8)from the Y color difference domain into the RGB domain. The inverse OETFunit 362 performs inverse conversion of grayscale compression on the HDRvideo signal output from the de-formatter 361 on the basis of OETFinformation (OETF) that is part of the HDR adjustment parameterinformation, and thereby obtains a linear HDR video signal.

The remove black-level unit 363 returns a black level of the linear HDRvideo signal output from the inverse OETF unit 362 to the state beforethe signal was adjusted by a black-level unit of the HDR cameraprocessing unit 315 (see FIG. 8) on the basis of information forblack-level correction (HDR-Black) that is part of the HDR adjustmentparameter information.

Note that, since a configuration of the SDR camera processing unit 324is similar to that described with reference to FIG. 7, descriptionthereof will be omitted here.

FIG. 10 illustrates a detailed configuration example of an HDR converter36 and an HDR converter 46. Here, an example in which the HDR converter36 converts an HDR-B video signal into an HDR-A video signal, and theHDR converter 46 converts an HDR-A video signal into an HDR-B videosignal is shown.

The HDR converter 36 has a de-formatter unit 370, an inverse OETF-B unit371, an OOTF-B unit 372, an inverse OOTF-A unit 373, and anOETF-A⋅formatter unit 374.

The de-formatter unit 370 performs a process of converting an inputHDR-B video signal “HDR OETF-B” that has undergone the grayscalecompression process of the signal interface B from the Y colordifference domain into the RGB domain. The inverse OETF-B unit 371performs the grayscale decompression process corresponding to thegrayscale compression process of the signal interface B on the HDR videosignal output from the de-formatter unit 370. The grayscaledecompression process mentioned here is performed using inversecharacteristics of the opto-electrical transfer function (OETF) for thesignal interface B.

The OOTF-B unit 372 adds characteristics of the system gamma (OOTF) ofthe signal interface B to the linear HDR video signal output from theinverse OETF-B unit 371. The inverse OOTF-A unit 373 addscharacteristics that cancel out the characteristics of the system gamma(OOTF) of the signal interface A on the HDR video signal output from theOOTF-B unit 372.

The OETF-A⋅formatter unit 374 performs the grayscale compression processof the signal interface A on the HDR video signal output from theinverse OOTF-A unit 373. The grayscale compression process mentionedhere refers to a process of compressing a bit length from a linear areausing the opto-electrical transfer function (OETF) for the signalinterface A. In addition, the OETF-A⋅formatter unit 374 converts thegrayscale-compressed HDR video signal from the RGB domain into the Ycolor difference domain, obtains an HDR-A video signal “HDR OETF-A” thathas undergone the grayscale compression process of the signal interfaceA, and then transmits the signal to a transmission path 42.

The HDR converter 36 has the OOTF-B unit 372 and the inverse OOTF-A unit373 as described above. For this reason, in a case in which the HDR-Avideo signal “HDR OETF-A” obtained by the HDR converter 36 is monitoredon a monitor 45 corresponding to the signal interface A, a videodisplayed on the monitor 45 is identical to the video displayed on amonitor 51 corresponding to the signal interface B for monitoring theHDR-B video signal “HDR OETF-B” that is an input of the HDR converter36.

The HDR converter 46 has a de-formatter unit 375, an inverse OETF-A unit376, an OOTF-A unit 377, an inverse OOTF-B unit 378, and anOETF-B⋅formatter unit 379.

The de-formatter unit 375 performs a process of converting the HDR-Avideo signal “HDR OETF-A” that has undergone the grayscale compressionprocess of the signal interface A extracted by a switcher 38 from the Ycolor difference domain into the RGB domain. The inverse OETF-A unit 376performs the grayscale decompression process corresponding to thegrayscale compression process of the signal interface A on the HDR videosignal output from the de-formatter unit 375.

The grayscale decompression process mentioned here is performed usingthe inverse characteristics of the opto-electrical transfer function(OETF) for the signal interface A.

The OOTF-A unit 377 adds characteristics of the system gamma (OOTF) ofthe signal interface A to the linear HDR video signal output from theinverse OETF-A unit 376. The inverse OOTF-B unit 378 addscharacteristics that cancel out the characteristics of the system gamma(OOTF) of the signal interface B on the HDR video signal output from theOOTF-A unit 377.

The OETF-B⋅formatter unit 379 performs the grayscale compression processof the signal interface B on the HDR video signal output from theinverse OOTF-B unit 378. The grayscale compression process mentionedhere refers to a process of compressing a bit length from a linear areausing the opto-electrical transfer function (OETF) for the signalinterface B. In addition, the OETF-B⋅formatter unit 379 converts thegrayscale-compressed HDR video signal from the RGB domain into the Ycolor difference domain, obtains an HDR-B video signal “HDR OETF-B” thathas undergone the grayscale compression process of the signal interfaceB, and then outputs the signal.

The HDR-B video signal “HDR OETF-B” obtained by the HDR converter 46 asdescribed above can be monitored by a monitor 48 corresponding to thesignal interface B. The HDR converter 46 has the OOTF-A unit 377 and theinverse OOTF-B unit 378. For this reason, a video displayed on themonitor 48 is identical to the video displayed on the monitor 45 formonitoring the HDR-A video signal “HDR OETF-A” that is an input of theHDR converter 46.

FIG. 11 also illustrates a detailed configuration example of an HDRconverter 36 and an HDR converter 46. Here, an example in which the HDRconverter 36 converts an HDR-C video signal into an HDR-A video signal,and the HDR converter 46 converts an HDR-A video signal into an HDR-Cvideo signal is shown.

The HDR converter 36 has a de-formatter unit 380, an EOTF-C unit 281, aninverse OOTF-A unit 382, and an OETF-A⋅formatter unit 383.

The de-formatter unit 380 performs a process of converting an inputHDR-C video signal-C “HDR EOTF-C” that has undergone the grayscalecompression process of the signal interface C from the Y colordifference domain into the RGB domain. The EOTF-C unit 381 performs thegrayscale decompression process corresponding to the grayscalecompression process of the signal interface C on the HDR video signaloutput from the de-formatter unit 380. The grayscale decompressionprocess mentioned here is performed using the electro-optical transferfunction (EOTF) for the signal interface C. The inverse OOTF-A unit 382adds characteristics that cancel out the characteristics of the systemgamma (OOTF) of the signal interface A to the HDR video signal outputfrom the EOTF-C unit 281.

The OETF-A⋅formatter unit 383 performs the grayscale compression processof the signal interface A on the HDR video signal output from theinverse OOTF-A unit 382. The grayscale compression process mentionedhere refers to a process of compressing a bit length from a linear areausing the opto-electrical transfer function (OETF) for the signalinterface A. In addition, the OETF-A⋅formatter unit 383 converts thegrayscale-compressed HDR video signal from the RGB domain into the Ycolor difference domain, obtains an HDR-A video signal “HDR OETF-A” thathas undergone the grayscale compression process of the signal interfaceA, and then transmits the signal to a transmission path 42.

The HDR converter 36 does not have the inverse OOTF-C unit 126 (seeFIG. 1) but has the inverse OOTF-A unit 382 as described above. For thisreason, in a case in which the HDR-A video signal “HDR OETF-A” obtainedby the HDR converter 36 is monitored on a monitor 45 corresponding tothe signal interface A, a video displayed on the monitor 45 is identicalto the video displayed on the monitor 52 corresponding to the signalinterface C for monitoring the HDR-C video signal “HDR OETF-C” that isan input of the HDR converter 36.

The HDR converter 46 has a de-formatter unit 385, an inverse OETF-A unit386, an OOTF-A unit 387, and an inverse EOTF-C-formatter unit 388. Thede-formatter unit 385 performs a process of converting the HDR-A videosignal “HDR OETF-A” that has undergone the grayscale compression processof the signal interface A extracted by a switcher 38 from the Y colordifference domain into the RGB domain.

The inverse OETF-A unit 386 performs the grayscale decompression processcorresponding to the grayscale compression process of the signalinterface A on the HDR video signal output from the de-formatter unit385. The grayscale decompression process mentioned here is performedusing inverse characteristics of the opto-electrical transfer function(OETF) for the signal interface A. The OOTF-A unit 387 adds thecharacteristics of the system gamma (OOTF) of the signal interface A onthe linear HDR video signal output from the inverse OETF-A unit 386.

The inverse EOTF-C-formatter unit 388 performs the grayscale compressionprocess of the signal interface C on the HDR video signal output fromthe OOTF-A unit 387. The grayscale compression process mentioned hererefers to a process of compressing a bit length from a linear area usinginverse characteristics of the electro-optical transfer function (EOTF)for the signal interface C. In addition, the inverse EOTF-C-formatterunit 388 converts the grayscale-compressed HDR video signal from the RGBdomain to the Y color difference domain, and thereby obtains an HDR-Cvideo signal “HDR EOTF-C” that has undergone the grayscale compressionprocess of the signal interface C, and outputs the signal.

The HDR-C video signal “HDR EOTF-C” obtained by the HDR converter 46 asdescribed above can be monitored on a monitor 48 corresponding to thesignal interface C. The HDR converter 46 has the OOTF-A unit 387, butdoes not have the OOTF-C unit 126 (see FIG. 1) as described above. Forthis reason, the video displayed on the monitor 48 is identical to thevideo displayed on the monitor 45 for monitoring the HDR-A video signal“HDR OETF-A” that is an input of the HDR converter 46.

Note that, the HDR converter 46 is a processor including a circuit, forexample, an FPGA, an ASIC, or the like as described above. Although thevideo system 30 can also have the HDR converter 46 that converts theHDR-A video signal “HDR OETF-A” into the HDR-B video signal “HDR OETF-B”as illustrated in FIG. 10 described above and the HDR converter 46 thatconverts the HDR-A video signal “HDR OETF-A” into the HDR-C video signal“HDR EOTF-C” as illustrated in FIG. 11 described above in parallel, aconfiguration in which functions of one HDR converter 46 are used byswitching is also conceivable. In this case, only an output signalinterface is set by a user, and the setting of an input signal interfacemay be automatically converted on the basis of information of the HDRvideo signal added to the HDR-A video signal “HDR OETF-A.”

FIG. 12 illustrates a configuration example of the SDR converter 49. TheSDR converter 49 has a CPU 401, an inverse HDR camera processing(Inverse HDR-CAM Process) unit 402, and an SDR camera processing (SDRCAM Process) unit 403. The CPU 401 controls operations of each unit ofthe SDR converter 49.

The inverse HDR camera processing unit 402 is a processor including acircuit, for example, an FPGA, an ASIC, or the like, performs a processof converting the HDR-A video signal “HDR OETF-A” that has undergone thegrayscale compression process of the signal interface A extracted by theswitcher 38 from the Y color difference domain into the RGB domain,inverse conversion of grayscale compression, and the like, and therebyobtains a linear HDR video signal. This operation of the inverse HDRcamera processing unit 402 may be performed on the basis of theinformation of the HDR-A video signal added to the HDR-A video signal“HDR OETF-A” under control of the CPU 401.

The SDR camera processing unit 403 performs level (gain) conversion,color gamut conversion, knee correction, detail (contour) correction,gamma processing, and the like on the linear HDR video signal obtainedby the inverse HDR camera processing unit 402, then obtains andtransmits an SDR video signal. This operation of the SDR cameraprocessing unit 403 may be performed on the basis of information of theSDR video signal added to the HDR-A video signal “HDR OETF-A” undercontrol of the CPU 401.

FIG. 13 illustrates a detailed configuration example of the inverse HDRcamera processing unit 402 and the SDR camera processing unit 403. Notethat, this is an example in which the HDR video signal has a UHD (8K,4K, etc.) resolution, and the SDR camera processing unit 403 may have aresolution conversion unit.

The inverse HDR camera processing unit 402 has a de-formatter(De-Formatter) unit 421, an inverse OETF (Inverse-OETF) unit 422, and aremove black-level (Remove-Black-level) unit 423.

The de-formatter unit 421 performs a process of converting the HDR-Avideo signal “HDR OETF-A” that has undergone the grayscale compressionprocess of the signal interface A extracted by the switcher 38 from theY color difference domain into the RGB domain. The inverse OETF unit 422performs inverse conversion of the grayscale compression on the HDRvideos signal output from the de-formatter unit 421 on the basis of OETFinformation (OETF) that is part of the HDR adjustment parameterinformation, and thereby obtains a linear HDR video signal.

The remove black-level unit 423 returns a black level of the linear HDRvideo signal output from the inverse OETF unit 422 to the state beforethe signal was adjusted on the basis of information for black-levelcorrection (HDR-Black) that is part of the HDR adjustment parameterinformation.

The SDR camera processing unit 403 has a resolution conversion unit 431,an SDR gain adjustment unit 432, a linear matrix (Linear-Matrix) unit433, a black level (Black-level) unit 434, a knee (Knee)-detail (Detail)unit 435, and a gamma (Gamma)-formatter (Formatter) unit 436.

The resolution conversion unit 431 converts the resolution of the linearHDR video signal (Linear HDR Video) obtained by the inverse HDR cameraprocessing unit 402 from UHD into HD. The SDR gain adjustment unit 432may control a master gain of the linear HDR video signal whoseresolution has been converted into an HD resolution by the resolutionconversion unit 431 on the basis of information of a relative gain(Relative-Gain) that is part of parameter information regarding levelsof the SDR video and the HDR video, and may control a gain of signals ofeach of primary colors R, G, and B for adjusting white balance.

The linear-matrix unit 433 performs a linear matrix process for colorgamut conversion on the HDR video signal output from the SDR gainadjustment unit 432 on the basis of color gamut information (SDR-ColorGamut) that is part of SDR adjustment parameter information andinformation regarding colors of the SDR video. The black-level unit 434adjusts a black level of the HDR video signal output from thelinear-matrix unit 433 on the basis of information for black levelcorrection (SDR-Black) that is part of the SDR adjustment parameterinformation. The knee-detail unit 435 performs knee correction on theHDR video signal output from the black-level unit 434 on the basis ofinformation regarding knee correction (KNEE) that is part of the SDRadjustment parameter information, and further performs detail (contour)correction on the SDR video signal.

The gamma⋅formatter unit 436 performs gamma processing on the linear SDRvideo signal output from the knee-detail unit 435 on the basis ofinformation regarding compression of a dynamic range (SDR-Gamma) that ispart of SDR adjustment parameter information. In addition, thegamma⋅formatter unit 436 performs conversion of the signal from the RGBdomain into the Y color difference domain and thereby obtains an outputSDR video signal.

As described above, in the video system 30 illustrated in FIG. 5, theplurality of input apparatuses input the HDR-A video signal that hasundergone the grayscale compression process of the signal interface Athat is a reference signal interface (standard signal interface) to theswitcher 38, and a predetermined HDR video signal extracted by theswitcher 38 is an HDR-A video signal that undergoes the grayscalecompression process of the reference signal interface at all times.Thus, the plurality of input apparatuses can perform uniform videoadjustment in monitoring of the video on the monitor 45 corresponding tothe reference signal interface (standard signal interface).

In addition, in the HDR converter 46 of the video system 30 illustratedin FIG. 5, when an HDR video signal that has undergone the grayscalecompression process of another signal interface other than the signalinterface A is output, a process of adding the characteristics of thesystem gamma of the signal interface A is at least performed. Thus, in acase in which the HDR video signal that has undergone the grayscalecompression process of the other signal interface is monitored on themonitor 48 corresponding to the interface, the video can be madeidentical to a video of a case in which the above-describedpredetermined HDR video signal is monitored on the monitor compatiblewith the signal interface A (adjusted video).

Note that, although not described above, the HDR converter 36 of thevideo system 30 (see FIG. 5) according to the fourth embodiment may havea function of changing a video when an HDR-B video signal or an HDR-Cvideo signal is converted into an HDR-A video signal. In this case, theHDR converter 36 may have, for example, a signal processor 441 asillustrated in FIGS. 14(a) and (b).

FIG. 14(a) illustrates a configuration example of an HDR converter 36that converts an HDR-B video signal into an HDR-A video signal. FIG.14(b) illustrates a configuration example of an HDR converter 36 thatconverts an HDR-C video signal into an HDR-A video signal. For example,the signal processor 441 may have a function of manually adjustingbrightness as long as a video of the HDR-A video signal output from theHDR converter 36 can be made brighter. In addition, for example, thesignal processor 441 may have a function of manually adjusting color aslong as color of the HDR-A video signal output from the HDR converter 36can be changed.

In addition, as the HDR-B video signal and the HDR-C video signal inputto the HDR converters 36, video signals produced in a situation in whichan OOTF function is not provided on the monitor side can be consideredas illustrated in FIGS. 15(a) and (b). FIG. 15(a) is an example in whicha linear HDR signal from a camera 442 is processed by a camera controlunit (CCU) 443 and an HDR-X video signal “HDR OETF-X” that has undergonea grayscale compression process of a signal interface X is obtained,illustrating that a monitor 444 for monitoring the video signal does nothave an OOTF function. FIG. 15(b) is an example in which a linear HDRsignal from a storage 445 is processed by a video processor unit (BPU)446 and an HDR-X video signal “HDR OETF-X” that has undergone thegrayscale compression process of the signal interface X is obtained,illustrating that a monitor 447 for monitoring the video signal does nothave an OOTF function.

In this case, the following case (1) and case (2) are conceivable.

Case (1): A video, simply as material data of a video, of a case inwhich no adjustment (so-called post-production) is performed for thevideo, only capturing of a camera video being performed.

Case (2): A video of a case in which all operations including adjustinghow the video appears are included in video adjustment in a monitorviewing environment without an OOTF.

Although there is no particular problem in the case of Case (1), in thecase of Case (2), it should be judged that the video includescharacteristics of system gamma (OOTF-x). In addition, in the case ofthe signal interface defined with the electro-optical transfer function(EOTF), for example, the signal interface C, the process of adding thesystem gamma (OOTF) is not performed on the monitor side originally, andthus the cases can be regarded as being equivalent.

Even in a case in which the process of adding the system gamma (OOTF) isnot actually performed in signal processing on the output side of theUDR-C video signal as illustrated in FIGS. 16(a) and (b), it should bejudged that characteristics of the system gamma (OOTF) are beingconsidered in a case corresponding to Case (2) (a case in which a videoon the monitor is a completed video).

Note that, FIG. 16(a) is an example in which a linear HDR signal from acamera 451 is processed by a camera control unit (CCU) 452 and therebyan HDR-C video signal is obtained, illustrating that the video signal isbeing monitored on a monitor 453 corresponding to the signal interfaceC. In addition, FIG. 16(b) is an example in which a linear HDR signalfrom a storage 454 is processed by a video processor unit (BPU) 455 andthereby an HDR-C video signal is obtained, illustrating that the videosignal is being monitored on a monitor 456 corresponding to the signalinterface C.

In the case of the above-described Case (1), the process of adding thecharacteristics of the system gamma (OOTF) is not performed in the HDRconverter 36 as illustrated in FIGS. 17(a) and (b), and signalprocessing may be performed in order to obtain a desired video in astandard monitoring environment of the signal interface A.

In addition, in the case of the above-described Case (2) with the signalinterface defined with the opto-electrical transfer function (OETF), forexample, only processes of converting signal interfaces of OETF/EOTF andcancelling out the system gamma (OOTF-A) of the signal interface A thatis a conversion destination may be performed, without performing theprocess of the system gamma (OOTF-B) of the signal interface B, asillustrated in FIG. 18(a).

In addition, in the case of the above-described Case (2) with the signalinterface defined with the electro-optical transfer function (EOTF), forexample, only processes of converting the signal interfaces of OETF/EOTFand cancelling out the system gamma (OOTF-A) of the signal interface Athat is a conversion destination may be performed as illustrated in FIG.18(b).

5. FIFTH EMBODIMENT [Configuration Example of HDR Production LiveSystem]

FIG. 19 illustrates a configuration example of an HDR production livesystem 500 as a fifth embodiment. The HDR production live system 500 hasa predetermined number of camera systems each including a camera and acamera control unit (CCU). In this embodiment, there are two camerasystems including a camera system having a camera 501 and a CCU 502 anda camera system having a camera 511 and a CCU 512.

The CCUs 502 and 512 performs processes of making images on capturedvideo signals from the cameras 501 and 511. High dynamic range (HDR)video signals (HDR-A video signals) that have undergone the grayscalecompression process of the signal interface A are obtained from the CCUs502 and 512. In this embodiment, the signal interface A is set as areference signal interface (standard signal interface). For example, thesignal interface A is “S-Log 3.”

In addition, the HDR production live system 500 has a server (Server)521 that performs recording and reproduction of a video file forreplay/reproduction and the like. Files recorded in the server 521include video files acquired by communication from an external apparatussuch as a personal computer (PC) in addition to files of video signals503 and 513 output from the CCUs 502 and 512.

The video signals 503 and 513 output from the CCUs 502 and 512 aretransmitted to the server 521 via a switcher 525, which will bedescribed below, as SDI signals. Information of the signal interface Ais added to, for example, a payload ID area and a VANC area of the SDIsignals as metadata. Accordingly, the server 521 can recognize that thevideo signals 503 and 513 output from the CCUs 502 and 512 are HDR-Avideo signals and the information of the signal interface A are added tofiles of the video signals 503 and 513 as attribute information. Notethat, the information of the signal interface is likewise added to avideo file input from an external apparatus such as a personal computer(PC), and accordingly the server 521 can recognize the signal interfacefor the video signal included in the file.

Here, a video signal input from an external apparatus such as a personalcomputer (PC) and included in a video file is not limited to theabove-described HDR-A video signal, and an HDR video signal that hasundergone the grayscale compression process of the signal interface B(HDR-B video signal), an HDR video signal that has undergone thegrayscale compression process of the signal interface C (HDR-C videosignal), or a standard dynamic range (SDR) video signal is conceivable.The signal interface B is, for example, “Hybrid Log-Gamma (HLG),” andthe signal interface C is “Perceptual Quantizer (PQ).”

In addition, the HDR production live system 500 has a monitor 523 forappropriately checking a video included in a file recorded in a storage537 in an operation by an operator of the server 521. A video signal 522corresponding to the signal interface corresponding to the monitor 523is transmitted from server 521 to the monitor 523 as an SDI signal. Inthis embodiment, the monitor 523 is, for example, an SDR monitor or anHDR monitor compatible with the signal interface B, and the monitor 523receives supply of an SDR video signal or an HDR-B video signal as thevideo signal 522 from the server 521.

In addition, the HDR production live system 500 has the switcher(Switcher) 525. The HDR-A video signals 503 and 513 output from the CCUs502 and 512 are input to the switcher 525 as SDI signals. As describedabove, information of the signal interface A is added to, for example, apayload ID area and a VANC area of the SDI signals as metadata.

In addition, a video signal 524 reproduced by the server 521 is alsoinput to the switcher 525. The video signal 524 is an HDR video signalthat has undergone the grayscale compression process of the signalinterface A (HDR-A video signal), and is transmitted from the server 521to the switcher 525 as an SDI signal. The information of the signalinterface A is added to, for example, a payload ID area and a VANC areaof the SDI signals as metadata.

The switcher 525 selectively extracts and outputs a predetermined HDR-Avideo signal from the HDR-A video signals input from the plurality ofinput apparatuses such as the camera systems, the servers 521, and thelike, or mixes and outputs an arbitrary video signal among the HDR-Avideo signals input from the plurality of input apparatuses. An HDR-Avideo signal 526 serving as a main line signal extracted by the switcher525 is output as an SDI signal without change.

The HDR production live system 500 has an HDR converter (HDR-Converter)527. The predetermined HDR-A video signal 526 extracted by the switcher525 is transmitted to the HDR converter 527 as an SDI signal. The HDRconverter 527 converts the HDR-A video signal into an HDR video signal528, for example, an HDR-B video signal or an HDR-C video signal andoutputs the signal. The HDR video signal 528 is output as an SDI signal.Information of the signal interface is added to, for example, a payloadID area and a VANC area of the SDI signal as metadata.

FIG. 20 illustrates a configuration example of the server 521. Solidline arrows in the drawing represent flows of signals, and dashed linearrows represent directions of controls. Although there are two inputsystems and two output systems in the illustrated example, the number ofsystems is not limited thereto.

The server 521 has a CPU 531, serial digital interface (SDI) input units532-1 and 532-2, encoders 533-1 and 533-2, decoders 534-1 and 534-2,opto-electrical transfer function (OETF) conversion units 535-1 and535-2, SDI output units 536-1 and 536-2, a storage 537, and acommunication interface 538.

The CPU 531 controls operations of each of the units of the server 521.The SDI input units 532-1 and 532-2 receive SDI signals and extractvideo signals and metadata from the SDI signals. The metadata alsoincludes information of signal interfaces of video signals included inthe SDI signals. The SDI input units 532-1 and 532-2 transmit themetadata extracted from the SDI signals to the CPU 531. Accordingly, theCPU 531 can recognize the signal interfaces of the video signalsincluded in the SDI signals.

The encoders 533-1 and 533-2 perform an encoding process in acompression format, for example, XAVC, or the like on the video signalsextracted from the SDI signals by the SDI input units 532-1 and 532-2and generate files (recording files). Note that, information of thesignal interfaces of the video signals are added to the files asattribute information. The files generated by the encoders 533-1 and533-2 are recorded in the storage 537 and reproduced under control ofthe CPU 531.

Here, the SDI input unit 532-1 and the encoder 533-1 constitute a firstinput system. In addition, the SDI input unit 532-1 receives the HDR-Avideo signal 503 output from the CCU 502 as an SDI signal. In addition,the SDI input unit 532-2 and the encoder 533-2 constitute a second inputsystem. In addition, the SDI input unit 532-2 receives the HDR-A videosignal 513 output from the CCU 512 as an SDI signal.

The communication interface 538 is, for example, an Ethernet interface,acquires files of past videos and computer graphic (CG) videos (videofiles) by communicating with a personal computer (PC) 550 as an externalapparatus, and transmits the files to the CPU 531. These files arerecorded in the storage 537 and reproduced under control of the CPU 531.Here, “Ethernet,” or “Ethernet” is a registered trademark.

The information of the signal interfaces of the video signals are alsoadded to the files as attribute information. In this case, the videosignals included in the files may be SDR video signals, and, if thesignals are HDR video signal, they are likely to correspond to varioussignal interfaces of an HDR-A video signal, an HDR-B video signal, anHDR-C video signal, and the like.

Note that, the CPU 531 can extract a file from the storage 537 andtransmit the file to the PC 550 through the communication interface 538.Accordingly, editing of the file and the like are performed with the PC550, and an edited file can also be returned to the storage 537.

The decoders 534-1 and 534-2 perform decoding processes on thereproduced files (video files) from the storage 537 and thereby obtainbaseband reproduction video signals. The reproduction video signals haveundergone a grayscale compression process corresponding to a firstsignal interface, including an HDR-A video signal, an HDR-B videosignal, an HDR-C video signal, an SDR video signal, and the like.

The OETF conversion units 535-1 and 535-2 perform OETF conversionprocesses on the reproduction video signal obtained by the decoders534-1 and 534-2 and obtain output video signals that have undergone agrayscale compression process corresponding to a second signal interfacethat is an output signal interface. Note that, the first signalinterface of the reproduction video signals is the same as the secondsignal interface of the output video signals, and the OETF conversionunits 535-1 and 535-2 set the reproduction video signals as output videosignals without change, performing no OETF conversion process.

The OETF conversion units 535-1 and 535-2 perform a process setting onthe basis of information of the first signal interface of thereproduction video signals and information of the second signalinterface of the output video signals. The processing setting by theOETF conversion units 535-1 and 535-2 is performed under control of theCPU 531. The CPU 531 can obtain the information of the first signalinterface of the reproduction video signals from the attributeinformation added to the files, and obtain the information of the secondsignal interface of the output video signals from information of thesetting made at the time of the system configuration.

The OETF conversion units 535-1 and 535-2 can each perform anindependent process setting. Here, the OETF conversion units 535-1 and535-2 change the process setting in accordance with a change of theinformation of the first signal interface of the reproduction videosignals when, for example, the reproduction video signals are obtainedin continuous reproduction of a plurality of files recorded in thestorage 537 as in playlist reproduction.

The SDI output units 536-1 and 536-2 output the output video signalsobtained by the OETF conversion units 535-1 and 535-2 as SDI signals. Inthis case, the SDI output units 536-1 and 536-2 set the information ofthe second signal interface of the output video signals in, for example,a payload ID area or a VANC area of the SDI signals as metadata.

Here, the decoder 534-1, the OETF conversion unit 535-1, and the SDIoutput unit 536-1 constitute a first output system. In addition, theHDR-A video signal 524 to be transmitted to the switcher 525 is outputfrom the SDI output unit 536-1 as an SDI signal. In addition, thedecoder 534-2, the OETF conversion unit 535-2, and the SDI output unit536-2 constitute a second output system. In addition, an SDR videosignal or an HDR-B video signal to be transmitted to the monitor 523 isoutput from the SDI output unit 536-2 as an SDI signal 522.

FIG. 21 illustrates a configuration example of the OETF conversion unit535 (535-1 or 535-2). The OETF conversion unit 535 has a recording-timeinverse OETF unit 541, a recording-time OOTF unit 542, a color gamutconversion unit 543, a linear gain unit 544, an output inverse OOTF unit545, and an output OETF unit 546. Here, description will be provided onthe assumption that the reproduction video signal is a video signal of asignal interface X, and the output video signal is a video signal of asignal interface Y.

The recording-time inverse OETF unit 541 performs a grayscaledecompression process corresponding to a grayscale compression processof the signal interface X performed on the reproduction video signal onthe reproduction video signal of the signal interface X. The grayscaledecompression process mentioned here is performed using inversecharacteristics of the opto-electrical transfer function (OETF) for thesignal interface X. The recording-time OOTF unit 542 addscharacteristics of system gamma (OOTF) of the signal interface X on theoutput video signal of the recording-time inverse OETF unit 541.

The color gamut conversion unit 543 performs a linear matrix process forcolor gamut conversion on the output video signal of the recording-timeOOTF unit 542. The linear gain unit 544 performs a gain adjustmentprocess on the output video signal of the color gamut conversion unit543. The color gamut conversion unit 543 is necessary only in a case inwhich conversion of color gamut between the reproduction video signaland the output video signal is necessary. In addition, the linear gainunit 544 is necessary in a case in which conversion from SDR to HDR orconversely from HDR to SDR is performed between the reproduction videosignal and the output video signal.

The output inverse OOTF unit 545 adds characteristics that cancel outcharacteristics of system gamma (OOTF) of the signal interface Y on theoutput video signal of the linear gain unit 544. The output OETF unit546 performs a grayscale compression process of the signal interface Yon the output video signal of the output inverse OOTF unit 545. Thegrayscale compression process mentioned here is performed usingcharacteristics of the opto-electrical transfer function (OETF) for thesignal interface Y.

In the OETF conversion unit 535, the recording-time inverse OETF unit541 and the recording-time OOTF unit 542 are set on the basis of thesignal interface X of the reproduction video signal, and the outputinverse OOTF unit 545 and the output OETF unit 546 are set on the basisof the signal interface Y of the output video signal. Accordingly, theoutput OETF conversion unit 535 obtains the output video signal that hasundergone the grayscale compression process of the signal interface Yfrom the reproduction video signal that has undergone the grayscalecompression process of the signal interface X.

FIG. 22 illustrates representative examples of actual set values of theOETF conversion unit 535 (see FIG. 21). The example (a) is an example ofa case in which the signal interface of the reproduction video signal(recording-time OETF) is “S-Log3,” and the signal interface of theoutput video signal (output OETF) is “SDR.” In addition, the color gamutof the reproduction video signal is “BT.2020” and the color gamut of theoutput video signal is “BT.709” in that case. This example is used foran OETF conversion process on the server 521 side in a case in which,for example, the monitor 523 is an SDR monitor.

In the case of the example (a), the recording-time inverse OETF unit 541is set to perform the grayscale decompression process (S-Log 3 InverseOETF) of “S-Log3.” The recording-time OOTF unit 542 is set to addcharacteristics of system gamma (OOTF) of “S-Log 3.” The color gamutconversion unit 543 is set to perform the linear matrix process ofconverting the color gamut from “BT.2020” to “BT.709.” The linear gainunit 544 is set to lower a gain from an HDR gain to an SDR gain. Theoutput inverse OOTF unit 545 is set to perform no process, that is, tooutput an input without change. Furthermore, the output OETF unit 546 isset to perform the grayscale compression process of “SDR” (SDR InverseEOTF).

In addition, the example (b) is an example in which the signal interfaceof the reproduction video signal (recording-time OETF) is “SDR” and thesignal interface of the output video signal (output OETF) is “S-Log 3.”In addition, the color gamut of the reproduction video signal is“BT.709” and the color gamut of the output video signal is “BT.2020” inthat case. This example is used in a case in which, for example, a filefrom the storage 537 including a video signal of which the signalinterface is for “SDR” is reproduced and a video signal of “S-Log 3” isinput to the switcher 525.

In the case of the example (b), the recording-time inverse OETF unit 541is set to perform the grayscale decompression process of “SDR” (SDREOTF). The recording-time OOTF unit 542 is set to perform no process,that is, to output an input without change. The color gamut conversionunit 543 is set to perform a linear matrix process of converting thecolor gamut from “BT.709” to “BT.2020.” The linear gain unit 544 is setto increase a gain from an SDR gain to an HDR gain. The output inverseOOTF unit 545 is set to cancel out the characteristics of the systemgamma (OOTF) of “S-Log 3.” Furthermore, the output OETF unit 546 is setto perform the grayscale compression process of “S-Log 3” (S-Log 3OETF).

In addition, the example (c) is an example in which the signal interfaceof the reproduction video signal (recording-time OETF) is “HLG” and thesignal interface of the output video signal (output OETF) is “S-Log 3.”In addition, the color gamut of the reproduction video signal is“BT.2020” and the color gamut of the output video signal also is“BT.2020” in that case. This example is used in a case in which, forexample, a file from the storage 537 including a video signal of whichthe signal interface is for “HLG” is reproduced and a video signal of“S-Log 3” is input to the switcher 525.

In the case of the example (c), the recording-time inverse OETF unit 541is set to perform a grayscale decompression process of “HLG” (HLGInverse OETF). The recording-time OOTF unit 542 is set to addcharacteristics of system gamma (OOTF) of “HLG.” The color gamutconversion unit 543 is set to perform no process, that is, to output aninput without change. The linear gain unit 544 is set to perform noprocess, that is, to output an input without change. The output inverseOOTF unit 545 is set to cancel out the characteristics of the systemgamma (OOTF) of “S-Log 3.” Furthermore, the output OETF unit 546 is setto perform the grayscale compression process of “S-Log 3” (S-Log 3OETF).

In addition, the example (d) is an example in which the signal interfaceof the reproduction video signal (recording-time OETF) is “PQ” and thesignal interface of the output video signal (output OETF) is “S-Log 3.”In addition, the color gamut of the reproduction video signal is“BT.2020” and the color gamut of the output video signal also is“BT.2020” in that case. This example is used in a case in which, forexample, a file from the storage 537 including a video signal of whichthe signal interface is for “PQ” is reproduced and a video signal of“S-Log 3” is input to the switcher 525.

In the case of the example (d), the recording-time inverse OETF unit 541is set to perform a grayscale decompression process of “PQ” (PQ EOTF).The recording-time OOTF unit 542 is set to perform no process, that is,to output an input without change. The color gamut conversion unit 543is set to perform no process, that is, to output an input withoutchange. The linear gain unit 544 is set to perform no process, that is,to output an input without change. The output inverse OOTF unit 545 isset to cancel out the characteristics of the system gamma (OOTF) of“S-Log3.” Furthermore, the output OETF unit 546 is set to perform thegrayscale compression process of “S-Log 3” (S-Log 3 OETF).

The flowchart of FIG. 23 illustrates an example of a control process ofthe OETF conversion unit 535 (535-1 or 535-2) by the CPU 531 in a casein which files having varying material information (signal interfaceinformation) from the storage 537 are continuously reproduced.

First, the CPU 531 acquires an EOTF setting of an output port, that is,information of a signal interface of an output video signal in StepS401. The CPU 531 acquires the information from, for example, theinformation of the setting made at the time of the system configuration.Next, the CPU 531 performs a process setting of the output inverse OOTFunit 545 and the output OETF unit 546 on the basis of the EOTF settingof the output port in Step S402.

Next, the CPU 531 acquires attributes of the material to be reproduced,that is, information of the signal interface of the reproduction videosignal, in Step S403. The CPU 531 acquires this information from, forexample, attribute information added to the files. Next, the CPU 531performs a process setting of the recording-time inverse OETF unit 541and the recording-time OOTF unit 542 on the basis of the attributes ofthe material to be reproduced in Step S404.

Next, in Step S405, the CPU 531 performs a process setting of the colorgamut conversion unit 543 and the linear gain unit 544 on the basis ofthe EOTF setting of the output port acquired in Step S401 and theattributes of the material to be reproduced acquired in Step S403. Then,the CPU 531 performs a reproduction process in Step S406.

In addition, the CPU 531 determines whether or not there is a materialchange in Step ST407. The CPU 531 can make this determination on thebasis of the attribute information added to the file of the material tobe reproduced. When it is determined that that is not a material change,the CPU 531 returns to the process of Step S406. On the other hand, whenit is determined that that is a material change, the CPU 531 returns tothe process of Step S403, performs the process setting of each of theunits as described above, and performs a reproduction process.

In the HDR production live system 500 introduced in the above-describedfifth embodiment, the server 521 includes the OETF conversion units 535(535-1 and 535-2) that convert the reproduction video signal that hasundergone the grayscale compression process corresponding to the firstsignal interface into the output video signal that has undergone thegrayscale compression process corresponding to the second signalinterface in the output system (reproduction system).

Therefore, also in a case in which a material having varying attributes(signal interfaces) from the storage 537 is continuously reproduced,video signals having the signal interfaces can be output in accordancewith the setting of the output port. For this reason, work of preparingthe signal interfaces when a material is stored in advance isunnecessary, thus a working time can be dramatically reduced,decoding/encoding of a codec at the time of conversion of signalinterfaces are also unnecessary, and therefore degradation of imagequality can be avoided.

6. MODIFIED EXAMPLES

Note that, in the above-described third embodiment, the example in whichthe OETF conversion units 535 (535-1 and 535-2) are provided in theserver 521 that converts the reproduction video signal that hasundergone the grayscale compression process corresponding to the firstsignal interface into the output video signal that has undergone thegrayscale compression process corresponding to the second signalinterface has been introduced. A configuration in which a similar OETFconversion unit is provided in the switcher 525 to convert areproduction video signal that has undergone the grayscale compressionprocess corresponding to the first signal interface into an output videosignal that has undergone the grayscale compression processcorresponding to the second signal interface in the switcher 525 is alsoconceivable.

In addition, although the signal interface A, for example, “S-Log 3” isset as a reference signal interface (standard signal interface) in theabove-described embodiments, a reference signal interface is not limitedthereto. The signal interface B, for example “Hybrid Log-Gamma (HLG),”or the signal interface C, for example, “Perceptual Quantizer (PQ)” maybe set as a reference signal interface (standard signal interface).

In addition, although the example in which the present technology isapplied to a camera system or a video system that deals with signalinterfaces A to C of three types has been introduced in theabove-described embodiment, the present technology can of course besimilarly applied to a camera system, a video system, or the like thatdeals with a plurality of types of signal interfaces, together with orseparately from the aforementioned signal interfaces.

Additionally, the present technology may also be configured as below.

(1)

A signal processing device including:

a processing unit configured to process a linear high dynamic rangevideo signal and obtain a high dynamic range video signal that hasundergone a grayscale compression process,

in which the processing unit is able to perform grayscale compressionprocesses of a plurality of signal interfaces.

(2)

The signal processing device according to (1),

in which the processing unit further performs at least a process ofadding characteristics of system gamma of a reference signal interfacewhen a grayscale compression process of another signal interface otherthan the reference signal interface is performed.

(3)

A signal processing method including:

a processing step of, by a processing unit, processing a linear highdynamic range video signal and obtaining a high dynamic range videosignal that has undergone a grayscale compression process,

in which the processing unit is able to perform grayscale compressionprocesses of a plurality of signal interfaces.

(4)

A camera system including:

an imaging unit configured to obtain a linear high dynamic range videosignal; and

a processing unit configured to process the linear high dynamic rangevideo signal and thereby obtain a high dynamic range video signal thathas undergone a grayscale compression process,

in which the processing unit is able to perform grayscale compressionprocesses of a plurality of signal interfaces.

(5)

A signal processing device including:

a processing unit configured to process a linear high dynamic rangevideo signal and thereby obtain a high dynamic range video signal thathas undergone a grayscale compression process of a reference signalinterface; and

a signal conversion unit configured to convert the high dynamic rangevideo signal that has undergone the grayscale compression process of thereference signal interface into a high dynamic range video signal thathas undergone a grayscale compression process of another signalinterface other than the reference signal interface,

in which the signal conversion unit performs each process of a grayscaledecompression process corresponding to the grayscale compression processof the reference signal interface, a process of adding characteristicsof system gamma of the reference signal interface and a process ofcancelling out characteristics of system gamma of another signalinterface, and a grayscale compression process of the other signalinterface on the high dynamic range video signal that has undergone thegrayscale compression process of the reference signal interface.

(6)

A signal processing method including:

a processing step of, by a processing unit, processing a linear highdynamic range video signal and thereby obtaining a high dynamic rangevideo signal that has undergone a grayscale compression process of areference signal interface;

a signal conversion step of, by a signal conversion unit, converting thehigh dynamic range video signal that has undergone the grayscalecompression process of the reference signal interface into a highdynamic range video signal that has undergone a grayscale compressionprocess of another signal interface other than the reference signalinterface,

in which, in the signal conversion step, the high dynamic range videosignal that has undergone the grayscale compression process of thereference signal interface undergoes at least each process of agrayscale decompression process corresponding to the grayscalecompression process of the reference signal interface, a process ofadding characteristics of system gamma of the reference signalinterface, and a grayscale compression process of the other signalinterface.

(7)

A camera system including:

an imaging unit configured to obtain a linear high dynamic range videosignal;

a processing unit configured to process the linear high dynamic rangevideo signal and thereby obtain a high dynamic range video signal thathas undergone a grayscale compression process of a reference signalinterface; and

a signal conversion unit configured to convert the high dynamic rangevideo signal that has undergone the grayscale compression process of thereference signal interface into a high dynamic range video signal thathas undergone a grayscale compression process of another signalinterface other than the reference signal interface,

in which the signal conversion unit performs at least each process of agrayscale decompression process corresponding to the grayscalecompression process of the reference signal interface, a process ofadding characteristics of system gamma of the reference signalinterface, and a grayscale compression process of the other signalinterface on the high dynamic range video signal that has undergone thegrayscale compression process of the reference signal interface.

(8)

A video system including:

an input unit including a plurality of input apparatuses that input ahigh dynamic range video signal that has undergone a grayscalecompression process of a reference signal interface;

an extraction unit configured to selectively extract a predeterminedhigh dynamic range video signal from the plurality of input apparatuses;and

an output unit configured to output a video signal based on thepredetermined high dynamic range video signal,

in which the output unit is able to output at least a high dynamic rangevideo signal that has undergone a grayscale compression process ofanother signal interface other than the reference signal interface, inaddition to the high dynamic range video signal that has undergone thegrayscale compression process of the reference signal interface, and

the output unit obtains the high dynamic range video signal that hasundergone the grayscale compression process of the other signalinterface by performing at least each process of a grayscaledecompression process corresponding to the grayscale compression processof the reference signal interface, a process of adding characteristicsof system gamma of the reference signal interface, and the grayscalecompression process of the other signal interface on the predeterminedhigh dynamic range video signal when the high dynamic range video signalthat has undergone the grayscale compression process of the other signalinterface is to be output.

(9)

The video system according to (8),

in which the input unit includes a camera system,

the camera system includes

an imaging unit configured to obtain a linear high dynamic range videosignal, and

a processing unit configured to process the linear high dynamic rangevideo signal and thereby obtain a high dynamic range video signal thathas undergone the grayscale compression process of the reference signalinterface.

(10)

The video system according to (8) or (9),

in which the input unit includes a signal conversion unit that convertsthe high dynamic range video signal that has undergone the grayscalecompression process of the other signal interface other than thereference signal interface into the high dynamic range video signal thathas undergone the grayscale compression process of the reference signalinterface, and

the signal conversion unit performs at least each process of thegrayscale decompression process corresponding to the grayscalecompression process of the other signal interface, a process of adding acharacteristic that cancels out the characteristics of system gamma ofthe reference signal interface, and the grayscale compression process ofthe reference signal interface on the high dynamic range video signalthat has undergone the grayscale compression process of the other signalinterface.

(11)

The video system according to any of (8) to (10),

in which the output unit is able to further output a standard dynamicrange video signal.

(12)

The video system according to (11),

in which information of the predetermined high dynamic range videosignal and information of the standard dynamic range video signalproduced on the basis of the predetermined high dynamic range videosignal are added to the predetermined high dynamic range video signal,and

the output unit processes the predetermined high dynamic range videosignal on the basis of the information added to the predetermined highdynamic range video signal and thereby obtains the standard dynamicrange video signal when the standard dynamic range video signal is to beoutput.

(13)

A server including:

a reproduction unit configured to reproduce a file recorded in a storageand obtain a reproduction video signal that has undergone a grayscalecompression process corresponding to a first signal interface; and

a processing unit configured to process the reproduction video signaland obtain an output video signal that has undergone a grayscalecompression process corresponding to a second signal interface.

(14)

The server according to (13),

in which the processing unit performs a process setting on the basis ofinformation of the first signal interface of the reproduction videosignal and information of the second signal interface of the outputvideo signal.

(15)

The server according to (14),

in which, when the reproduction video signal is obtained in continuousreproduction of a plurality of files recorded in the storage, theprocessing unit changes the process setting in accordance with a changeof the information of the first signal interface of the reproductionvideo signal.

(16)

The server according to any of (13) to (15), including:

a plurality of output systems of the reproduction unit and theprocessing unit,

in which the processing units of the plurality of output systems areable to each perform an independent process setting.

(17)

The server according to any of (13) to (16), further including:

an information superimposing unit configured to superimpose informationof the second signal interface on the output video signal.

REFERENCE SIGNS LIST

-   10A, 10B, 10C camera system-   11 camera-   12, 12B, 12C camera control unit-   13 camera cable-   14 communication path-   15 control panel-   16, 17, 18 monitor-   19, 20 HDR converter-   30 video system-   31 camera-   32 camera control unit-   33 camera cable-   34 communication path-   35 control panel-   36 HDR converter-   37 server-   38 switcher-   39, 40, 42, 44, 47 transmission path-   41 SDR monitor-   43 main transmission path-   45, 48, 51, 52 monitor-   46 HDR converter-   49 SDR converter-   111 CPU-   112 imaging unit-   113 pre-processing unit-   114 transmission unit-   121 CPU-   122 transmission unit-   123 HDR camera processing unit-   124 OETF-A⋅formatter unit-   125 OETF-B⋅formatter unit-   126 OOTF-C unit-   127 inverse EOTF-C-formatter unit-   131 HDR gain adjustment unit-   132 linear matrix unit-   133 black-level unit-   134 detail unit-   141, 143 OOTF-A unit-   142 inverse OOTF-B unit-   144, 146 de-formatter unit-   145, 147 inverse OETF-A unit-   311 CPU-   312 imaging unit-   313 pre-processing unit-   314 transmission unit-   315 HDR camera processing unit-   321 CPU-   322 transmission unit-   323 HDR camera processing unit-   324 SDR camera processing unit-   325 inverse HDR camera processing unit-   331 HDR gain adjustment unit-   332 linear matrix unit-   333 black-level unit-   334 detail unit-   335 OETF-A⋅formatter unit-   341 resolution conversion unit-   342 SDR gain adjustment unit-   343 linear matrix unit-   344 black-level unit-   345 knee-detail unit-   346 gamma⋅formatter unit-   351 CPU-   352 operation input unit-   361 de-formatter unit-   362 inverse OETF unit-   363 remove black-level unit-   370 de-formatter unit-   371 inverse OETF-B unit-   372 OOTF-B unit-   373 inverse OOTF-A unit-   374 OETF-A⋅formatter unit-   375 de-formatter unit-   376 inverse OETF-A unit-   377 OOTF-A unit-   378 inverse OOTF-B unit-   379 OETF-B⋅formatter unit-   380 de-formatter unit-   381 EOTF-C unit-   382 inverse OOTF-Aunit-   383 OETF-A⋅formatter unit-   385 de-formatter unit-   386 inverse OETF unit-   387 OOTF-A unit-   388 inverse EOTF-C-formatter unit-   401 CPU-   402 inverse HDR camera processing unit-   403 SDR camera processing unit-   421 SDR de-formatter unit-   422 inverse OETF unit-   423 remove black-level unit-   431 resolution conversion unit-   432 SDR gain adjustment unit-   433 linear matrix unit-   434 black-level unit-   435 knee-detail unit-   436 gamma⋅formatter unit-   441 signal processor-   442 camera-   443 camera control unit-   444, 447 monitor-   445 storage-   446 video processor unit-   451 camera-   452 camera control unit-   453,456 monitor-   454 storage-   455 video processor unit-   500 HDR production live system-   501, 511 camera-   502, 512 camera control unit-   521 server-   523 monitor-   525 switcher-   527 HDR converter-   531 CPU-   532-1, 532-2 SDI input unit-   533-1, 533-2 encoder-   534-1, 534-2 decoder-   535-1, 535-2 OETF conversion unit-   536-1, 536-2 SDI output unit-   537 storage-   538 communication interface-   541 recording-time inverse OETF unit-   542 recording-time OOTF unit-   543 color gamut conversion unit-   544 linear gain unit-   545 output inverse OOTF unit-   546 output OETF unit-   550 personal computer

1-17. (canceled)
 18. A signal processing system, comprising: one or moreprocessors configured to: apply a first optical-optical transferfunction (OOTF) conversion corresponding to a first signal interface toan input linear video signal, and apply a grayscale compression processcorresponding to a second signal interface which is different from thefirst signal interface.
 19. The signal processing system according toclaim 18, wherein the one or more processors are further configured toapply a second OOFT conversion corresponding to the second signalinterface to an output of the grayscale compression process.
 20. Thesignal processing system according to claim 18, wherein the one or moreprocessors are further configured to apply an inverse grayscalecompression process between the first OOTF conversion and the grayscalecompression process.
 21. The signal processing system according to claim18, wherein the one or more processors are configured to apply aninverse grayscale compression process corresponding to the second signalinterface to an output of the first OOTF conversion process.
 22. Thesignal processing system according to claim 18, wherein the one or moreprocessors are further configured to apply the first OOTF conversioncorresponding to the first signal interface to an output of thegrayscale compression process.
 23. The signal processing apparatusaccording to claim 22, wherein the one or more processors are furtherconfigured to apply the first OOTF conversion corresponding to the firstsignal interface to an output of the grayscale compression process in amonitor.
 24. The signal processing system according to claim 19, whereinthe one or more processors are further configured to apply the firstOOTF conversion corresponding to the first signal interface to an outputof the grayscale compression process.
 25. The signal processing systemaccording to claim 24, wherein the one or more processors are configuredto selectively output an output of the first OOTF conversion or anoutput of the second OOTF conversion.
 26. The signal processing systemaccording to claim 24, wherein the one or more processors are furtherconfigured to output an output of the first OOTF conversion and anoutput of the second OOTF conversion in parallel.
 27. The signalprocessing system according to claim 18, wherein the first OOTFconversion is performed by adding a system gamma.
 28. The signalprocessing system according to claim 18, wherein the one or moreprocessors are configured to apply the first OOTF conversion and thegrayscale compression process in a camera controller.
 29. The signalprocessing system according to claim 18, wherein the first signalinterface is a reference signal interface.
 30. The signal processingsystem according to claim 18, wherein each of the first signal interfaceand the second signal interface is a signal interface for high dynamicrange (HDR) video signals.
 31. The signal processing system according toclaim 30, wherein the second signal interface is one of a hybridlog-gamma (HLG) or perceptual quantizer (PQ).
 32. The signal processingsystem according to claim 18, wherein the one or more processors areconfigured to apply a grayscale compression process corresponding to athird signal interface which is different from the first and the secondsignal interfaces.
 33. The signal processing system according to claim18, wherein the input linear video signal is a high dynamic range (HDR)signal.
 34. The signal processing system according to claim 18, furthercomprising a control panel configured to receive user input.
 35. Asignal processing method, comprising: applying, with one or moreprocessors, a first optical-optical transfer function (OOTF) conversioncorresponding to a first signal interface to an input linear videosignal; and applying, with the one or more processors, a grayscalecompression process corresponding to a second signal interface which isdifferent from the first signal interface.
 36. A non-transitorycomputer-readable medium encoded with computer-readable instructionsthat, when executed by one or more processors, cause the one or moreprocessors to perform a method comprising: applying a firstoptical-optical transfer function (OOTF) conversion corresponding to afirst signal interface to an input linear video signal; and applying agrayscale compression process corresponding to a second signal interfacewhich is different from the first signal interface.